1639394025640 has 64 divisors (see below), whose sum is σ = 4230586920960. Its totient is φ = 560077647360.

The previous prime is 1639394025637. The next prime is 1639394025701. The reversal of 1639394025640 is 465204939361.

It is a super-2 number, since 2×1639394025640² (a number of 25 digits) contains 22 as substring.

It is an unprimeable number.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 10339432 + ... + 10496791.

It is an arithmetic number, because the mean of its divisors is an integer number (66102920640).

Almost surely, 2^{1639394025640} is an apocalyptic number.

1639394025640 is a gapful number since it is divisible by the number (10) formed by its first and last digit.

It is an amenable number.

1639394025640 is an abundant number, since it is smaller than the sum of its proper divisors (2591192895320).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

1639394025640 is a wasteful number, since it uses less digits than its factorization.

1639394025640 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 20836522 (or 20836518 counting only the distinct ones).

The product of its (nonzero) digits is 4199040, while the sum is 52.

The spelling of 1639394025640 in words is "one trillion, six hundred thirty-nine billion, three hundred ninety-four million, twenty-five thousand, six hundred forty".