79997640 has 32 divisors (see below), whose sum is σ = 239993280. Its totient is φ = 21332672.

The previous prime is 79997633. The next prime is 79997647. The reversal of 79997640 is 4679997.

It is an interprime number because it is at equal distance from previous prime (79997633) and next prime (79997647).

It is not an unprimeable number, because it can be changed into a prime (79997647) by changing a digit.

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 7 ways as a sum of consecutive naturals, for example, 333204 + ... + 333443.

It is an arithmetic number, because the mean of its divisors is an integer number (7499790).

Almost surely, 2^79997640 is an apocalyptic number.

It is an amenable number.

79997640 is an abundant number, since it is smaller than the sum of its proper divisors (159995640).

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

79997640 is a wasteful number, since it uses less digits than its factorization.

79997640 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 666661 (or 666657 counting only the distinct ones).

The product of its (nonzero) digits is 857304, while the sum is 51.

The square root of 79997640 is about 8944.1399810155. The cubic root of 79997640 is about 430.8827009098.

The spelling of 79997640 in words is "seventy-nine million, nine hundred ninety-seven thousand, six hundred forty".