79978637 has 4 divisors (see below), whose sum is σ = 81172416. Its totient is φ = 78784860.

The previous prime is 79978609. The next prime is 79978649. The reversal of 79978637 is 73687997.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4.

It is a cyclic number.

It is not a de Polignac number, because 79978637 - 2¹² = 79974541 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (79978837) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 596789 + ... + 596922.

It is an arithmetic number, because the mean of its divisors is an integer number (20293104).

Almost surely, 2^79978637 is an apocalyptic number.

It is an amenable number.

79978637 is a deficient number, since it is larger than the sum of its proper divisors (1193779).

79978637 is a wasteful number, since it uses less digits than its factorization.

79978637 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1193778.

The product of its digits is 4000752, while the sum is 56.

The square root of 79978637 is about 8943.0776022575. The cubic root of 79978637 is about 430.8485802683.

The spelling of 79978637 in words is "seventy-nine million, nine hundred seventy-eight thousand, six hundred thirty-seven".