640630032767 has 4 divisors (see below), whose sum is σ = 640710009576. Its totient is φ = 640550055960.

The previous prime is 640630032743. The next prime is 640630032797. The reversal of 640630032767 is 767230036046.

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 640630032767 - 2²⁸ = 640361597311 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 (640630032797) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 39976388 + ... + 39992409.

It is an arithmetic number, because the mean of its divisors is an integer number (160177502394).

Almost surely, 2^640630032767 is an apocalyptic number.

640630032767 is a deficient number, since it is larger than the sum of its proper divisors (79976809).

640630032767 is an equidigital number, since it uses as much as digits as its factorization.

640630032767 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 79976808.

The product of its (nonzero) digits is 762048, while the sum is 44.

The spelling of 640630032767 in words is "six hundred forty billion, six hundred thirty million, thirty-two thousand, seven hundred sixty-seven".