79641057438 has 128 divisors (see below), whose sum is σ = 189406080000. Its totient is φ = 24732905472.

The previous prime is 79641057337. The next prime is 79641057451. The reversal of 79641057438 is 83475014697.

79641057438 is a `hidden beast` number, since 7 + 9 + 64 + 1 + 0 + 574 + 3 + 8 = 666.

It is a Harshad number since it is a multiple of its sum of digits (54).

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 63 ways as a sum of consecutive naturals, for example, 17621343 + ... + 17625861.

It is an arithmetic number, because the mean of its divisors is an integer number (1479735000).

Almost surely, 2^79641057438 is an apocalyptic number.

It is a practical number, because each smaller number is the sum of distinct divisors of 79641057438, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (94703040000).

79641057438 is an abundant number, since it is smaller than the sum of its proper divisors (109765022562).

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

79641057438 is a wasteful number, since it uses less digits than its factorization.

79641057438 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 4831 (or 4825 counting only the distinct ones).

The product of its (nonzero) digits is 5080320, while the sum is 54.

The spelling of 79641057438 in words is "seventy-nine billion, six hundred forty-one million, fifty-seven thousand, four hundred thirty-eight".