640700039 has 6 divisors (see below), whose sum is σ = 745304184. Its totient is φ = 549171420.

The previous prime is 640700003. The next prime is 640700041. The reversal of 640700039 is 930007046.

It is not a de Polignac number, because 640700039 - 2²⁸ = 372264583 is a prime.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 640699984 and 640700020.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (640700059) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 5 ways as a sum of consecutive naturals, for example, 6537707 + ... + 6537804.

It is an arithmetic number, because the mean of its divisors is an integer number (124217364).

Almost surely, 2^640700039 is an apocalyptic number.

640700039 is a deficient number, since it is larger than the sum of its proper divisors (104604145).

640700039 is a wasteful number, since it uses less digits than its factorization.

640700039 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 13075525 (or 13075518 counting only the distinct ones).

The product of its (nonzero) digits is 4536, while the sum is 29.

The square root of 640700039 is about 25312.0532355635. The cubic root of 640700039 is about 862.0879674188.

The spelling of 640700039 in words is "six hundred forty million, seven hundred thousand, thirty-nine".