7971240 has 64 divisors (see below), whose sum is σ = 24111360. Its totient is φ = 2108160.

The previous prime is 7971239. The next prime is 7971251. The reversal of 7971240 is 421797.

It is a Harshad number since it is a multiple of its sum of digits (30).

It is a junction number, because it is equal to n+sod(n) for n = 7971198 and 7971207.

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 15 ways as a sum of consecutive naturals, for example, 21537 + ... + 21903.

It is an arithmetic number, because the mean of its divisors is an integer number (376740).

Almost surely, 2^7971240 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 7971240, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (12055680).

7971240 is an abundant number, since it is smaller than the sum of its proper divisors (16140120).

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

7971240 is a wasteful number, since it uses less digits than its factorization.

7971240 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 562 (or 558 counting only the distinct ones).

The product of its (nonzero) digits is 3528, while the sum is 30.

The square root of 7971240 is about 2823.3384494247. The cubic root of 7971240 is about 199.7600455578.

The spelling of 7971240 in words is "seven million, nine hundred seventy-one thousand, two hundred forty".