639694586965 has 64 divisors (see below), whose sum is σ = 916199424000. Its totient is φ = 419750472960.

The previous prime is 639694586953. The next prime is 639694586987. The reversal of 639694586965 is 569685496936.

It is not a de Polignac number, because 639694586965 - 2⁷ = 639694586837 is a prime.

It is a super-2 number, since 2×639694586965² (a number of 24 digits) contains 22 as substring.

It is a junction number, because it is equal to n+sod(n) for n = 639694586891 and 639694586900.

It is a congruent number.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 63 ways as a sum of consecutive naturals, for example, 11554971 + ... + 11610199.

It is an arithmetic number, because the mean of its divisors is an integer number (14315616000).

Almost surely, 2^639694586965 is an apocalyptic number.

It is an amenable number.

639694586965 is a deficient number, since it is larger than the sum of its proper divisors (276504837035).

639694586965 is a wasteful number, since it uses less digits than its factorization.

639694586965 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 55450.

The product of its digits is 2267481600, while the sum is 76.

The spelling of 639694586965 in words is "six hundred thirty-nine billion, six hundred ninety-four million, five hundred eighty-six thousand, nine hundred sixty-five".