640440036013 has 4 divisors (see below), whose sum is σ = 641229728608. Its totient is φ = 639650343420.

The previous prime is 640440036001. The next prime is 640440036053. The reversal of 640440036013 is 310630044046.

It is a happy number.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-640440036013 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (640440036053) 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, 394845081 + ... + 394846702.

It is an arithmetic number, because the mean of its divisors is an integer number (160307432152).

Almost surely, 2^640440036013 is an apocalyptic number.

It is an amenable number.

640440036013 is a deficient number, since it is larger than the sum of its proper divisors (789692595).

640440036013 is an equidigital number, since it uses as much as digits as its factorization.

640440036013 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 789692594.

The product of its (nonzero) digits is 20736, while the sum is 31.

The spelling of 640440036013 in words is "six hundred forty billion, four hundred forty million, thirty-six thousand, thirteen".