71774820 has 144 divisors (see below), whose sum is σ = 241091760. Its totient is φ = 17169408.

The previous prime is 71774771. The next prime is 71774873. The reversal of 71774820 is 2847717.

71774820 is a `hidden beast` number, since 7 + 177 + 482 + 0 = 666.

It can be written as a sum of positive squares in 8 ways, for example, as 36 + 71774784 = 6^2 + 8472^2 .

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

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 47 ways as a sum of consecutive naturals, for example, 86166 + ... + 86994.

Almost surely, 2^71774820 is an apocalyptic number.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 71774820, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (120545880).

71774820 is an abundant number, since it is smaller than the sum of its proper divisors (169316940).

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

71774820 is a wasteful number, since it uses less digits than its factorization.

71774820 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 894 (or 889 counting only the distinct ones).

The product of its (nonzero) digits is 21952, while the sum is 36.

The square root of 71774820 is about 8472.0021246456. The cubic root of 71774820 is about 415.5826142164.

Subtracting from 71774820 its sum of digits (36), we obtain a square (71774784 = 8472²).

The spelling of 71774820 in words is "seventy-one million, seven hundred seventy-four thousand, eight hundred twenty".