2638507979 has 4 divisors (see below), whose sum is σ = 2777376840. Its totient is φ = 2499639120.

The previous prime is 2638507919. The next prime is 2638508011. The reversal of 2638507979 is 9797058362.

It is a semiprime because it is the product of two primes.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-2638507979 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (2638507919) 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, 69434402 + ... + 69434439.

It is an arithmetic number, because the mean of its divisors is an integer number (694344210).

Almost surely, 2^2638507979 is an apocalyptic number.

2638507979 is a deficient number, since it is larger than the sum of its proper divisors (138868861).

2638507979 is a wasteful number, since it uses less digits than its factorization.

2638507979 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 138868860.

The product of its (nonzero) digits is 5715360, while the sum is 56.

The square root of 2638507979 is about 51366.4090529988. The cubic root of 2638507979 is about 1381.8242308622.

The spelling of 2638507979 in words is "two billion, six hundred thirty-eight million, five hundred seven thousand, nine hundred seventy-nine".