639592638561 has 16 divisors (see below), whose sum is σ = 947736929920. Its totient is φ = 426308566320.

The previous prime is 639592638551. The next prime is 639592638661. The reversal of 639592638561 is 165836295936.

639592638561 is a `hidden beast` number, since 6 + 3 + 9 + 5 + 9 + 2 + 63 + 8 + 561 = 666.

It is not a de Polignac number, because 639592638561 - 2¹⁴ = 639592622177 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (639592638541) by changing a digit.

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 15 ways as a sum of consecutive naturals, for example, 2267845 + ... + 2534226.

It is an arithmetic number, because the mean of its divisors is an integer number (59233558120).

Almost surely, 2^639592638561 is an apocalyptic number.

It is an amenable number.

639592638561 is a deficient number, since it is larger than the sum of its proper divisors (308144291359).

639592638561 is a wasteful number, since it uses less digits than its factorization.

639592638561 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 4807013 (or 4807007 counting only the distinct ones).

The product of its digits is 62985600, while the sum is 63.

The spelling of 639592638561 in words is "six hundred thirty-nine billion, five hundred ninety-two million, six hundred thirty-eight thousand, five hundred sixty-one".