640207036439 has 4 divisors (see below), whose sum is σ = 673902143640. Its totient is φ = 606511929240.

The previous prime is 640207036409. The next prime is 640207036493. The reversal of 640207036439 is 934630702046.

It is a semiprime because it is the product of two primes.

It is a cyclic number.

It is not a de Polignac number, because 640207036439 - 2²⁴ = 640190259223 is a prime.

It is a Duffinian number.

It is a self number, because there is not a number n which added to its sum of digits gives 640207036439.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (640207036409) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 16847553572 + ... + 16847553609.

It is an arithmetic number, because the mean of its divisors is an integer number (168475535910).

Almost surely, 2^640207036439 is an apocalyptic number.

640207036439 is a deficient number, since it is larger than the sum of its proper divisors (33695107201).

640207036439 is a wasteful number, since it uses less digits than its factorization.

640207036439 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 33695107200.

The product of its (nonzero) digits is 653184, while the sum is 44.

The spelling of 640207036439 in words is "six hundred forty billion, two hundred seven million, thirty-six thousand, four hundred thirty-nine".