84971520 has 156 divisors (see below), whose sum is σ = 295170876. Its totient is φ = 22609920.

The previous prime is 84971519. The next prime is 84971521. The reversal of 84971520 is 2517948.

It is an interprime number because it is at equal distance from previous prime (84971519) and next prime (84971521).

It can be written as a sum of positive squares in 2 ways, for example, as 28901376 + 56070144 = 5376^2 + 7488^2 .

It is a super-2 number, since 2×84971520² = 14440318422220800, which contains 22 as substring.

It is a Harshad number since it is a multiple of its sum of digits (36).

It is not an unprimeable number, because it can be changed into a prime (84971521) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (5) of ones.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 184090 + ... + 184550.

It is an arithmetic number, because the mean of its divisors is an integer number (1892121).

Almost surely, 2^84971520 is an apocalyptic number.

84971520 is a gapful number since it is divisible by the number (80) formed by its first and last digit.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 84971520, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (147585438).

84971520 is an abundant number, since it is smaller than the sum of its proper divisors (210199356).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

84971520 is a wasteful number, since it uses less digits than its factorization.

84971520 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 496 (or 471 counting only the distinct ones).

The product of its (nonzero) digits is 20160, while the sum is 36.

The square root of 84971520 is about 9217.9997830332. Note that the first 3 decimals coincide. The cubic root of 84971520 is about 439.6338551777.

It can be divided in two parts, 84971 and 520, that added together give a triangular number (85491 = T₄₁₃).

The spelling of 84971520 in words is "eighty-four million, nine hundred seventy-one thousand, five hundred twenty".