3638979421 has 64 divisors (see below), whose sum is σ = 5002145280. Its totient is φ = 2559836160.

The previous prime is 3638979413. The next prime is 3638979451. The reversal of 3638979421 is 1249798363.

It is not a de Polignac number, because 3638979421 - 2³ = 3638979413 is a prime.

It is a super-2 number, since 2×3638979421² = 26484342452922990482, which contains 22 as substring.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (3638979451) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written in 63 ways as a sum of consecutive naturals, for example, 9755791 + ... + 9756163.

It is an arithmetic number, because the mean of its divisors is an integer number (78158520).

Almost surely, 2^3638979421 is an apocalyptic number.

It is an amenable number.

3638979421 is a deficient number, since it is larger than the sum of its proper divisors (1363165859).

3638979421 is a wasteful number, since it uses less digits than its factorization.

3638979421 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 694.

The product of its digits is 1959552, while the sum is 52.

The square root of 3638979421 is about 60323.9539569481. The cubic root of 3638979421 is about 1538.1305562300.

The spelling of 3638979421 in words is "three billion, six hundred thirty-eight million, nine hundred seventy-nine thousand, four hundred twenty-one".