79745640 has 256 divisors, whose sum is σ = 284497920. Its totient is φ = 17694720.

The previous prime is 79745629. The next prime is 79745647. The reversal of 79745640 is 4654797.

It is a hoax number, since the sum of its digits (42) coincides with the sum of the digits of its distinct prime factors.

It is a junction number, because it is equal to n+sod(n) for n = 79745592 and 79745601.

It is not an unprimeable number, because it can be changed into a prime (79745647) by changing a digit.

It is a polite number, since it can be written in 63 ways as a sum of consecutive naturals, for example, 822072 + ... + 822168.

It is an arithmetic number, because the mean of its divisors is an integer number (1111320).

Almost surely, 2^79745640 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 79745640, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (142248960).

79745640 is an abundant number, since it is smaller than the sum of its proper divisors (204752280).

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

79745640 is a wasteful number, since it uses less digits than its factorization.

79745640 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 172 (or 168 counting only the distinct ones).

The product of its (nonzero) digits is 211680, while the sum is 42.

The square root of 79745640 is about 8930.0414332745. The cubic root of 79745640 is about 430.4297848175.

The spelling of 79745640 in words is "seventy-nine million, seven hundred forty-five thousand, six hundred forty".