640207036438 has 16 divisors (see below), whose sum is σ = 978595772976. Its totient is φ = 314010496800.

The previous prime is 640207036409. The next prime is 640207036493. The reversal of 640207036438 is 834630702046.

It is a happy number.

It is a junction number, because it is equal to n+sod(n) for n = 640207036394 and 640207036403.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 117988 + ... + 1137688.

It is an arithmetic number, because the mean of its divisors is an integer number (61162235811).

Almost surely, 2^640207036438 is an apocalyptic number.

640207036438 is a deficient number, since it is larger than the sum of its proper divisors (338388736538).

640207036438 is a wasteful number, since it uses less digits than its factorization.

640207036438 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1025679.

The product of its (nonzero) digits is 580608, while the sum is 43.

The spelling of 640207036438 in words is "six hundred forty billion, two hundred seven million, thirty-six thousand, four hundred thirty-eight".