640837401931 has 8 divisors (see below), whose sum is σ = 649629989360. Its totient is φ = 632045192832.

The previous prime is 640837401901. The next prime is 640837401949. The reversal of 640837401931 is 139104738046.

It is a sphenic number, since it is the product of 3 distinct primes.

It is a cyclic number.

It is not a de Polignac number, because 640837401931 - 2¹¹ = 640837399883 is a prime.

It is a super-2 number, since 2×640837401931² (a number of 24 digits) contains 22 as substring.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (640837401901) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 5923855 + ... + 6031063.

It is an arithmetic number, because the mean of its divisors is an integer number (81203748670).

Almost surely, 2^640837401931 is an apocalyptic number.

640837401931 is a deficient number, since it is larger than the sum of its proper divisors (8792587429).

640837401931 is a wasteful number, since it uses less digits than its factorization.

640837401931 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 189165.

The product of its (nonzero) digits is 435456, while the sum is 46.

The spelling of 640837401931 in words is "six hundred forty billion, eight hundred thirty-seven million, four hundred one thousand, nine hundred thirty-one".