638634070977 has 32 divisors (see below), whose sum is σ = 996194377728. Its totient is φ = 356301542016.

The previous prime is 638634070961. The next prime is 638634071017. The reversal of 638634070977 is 779070436836.

It is not a de Polignac number, because 638634070977 - 2⁴ = 638634070961 is a prime.

It is a super-2 number, since 2×638634070977² (a number of 24 digits) contains 22 as substring.

It is a self number, because there is not a number n which added to its sum of digits gives 638634070977.

It is not an unprimeable number, because it can be changed into a prime (638634072977) by changing a digit.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 2090128 + ... + 2376110.

It is an arithmetic number, because the mean of its divisors is an integer number (31131074304).

Almost surely, 2^638634070977 is an apocalyptic number.

It is an amenable number.

638634070977 is a deficient number, since it is larger than the sum of its proper divisors (357560306751).

638634070977 is a wasteful number, since it uses less digits than its factorization.

638634070977 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 288509.

The product of its (nonzero) digits is 32006016, while the sum is 60.

The spelling of 638634070977 in words is "six hundred thirty-eight billion, six hundred thirty-four million, seventy thousand, nine hundred seventy-seven".