640950775 has 12 divisors (see below), whose sum is σ = 829335312. Its totient is φ = 490466240.

The previous prime is 640950727. The next prime is 640950787. The reversal of 640950775 is 577059046.

640950775 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is not a de Polignac number, because 640950775 - 2⁹ = 640950263 is a prime.

It is a Duffinian number.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 556774 + ... + 557923.

It is an arithmetic number, because the mean of its divisors is an integer number (69111276).

Almost surely, 2^640950775 is an apocalyptic number.

640950775 is a deficient number, since it is larger than the sum of its proper divisors (188384537).

640950775 is a wasteful number, since it uses less digits than its factorization.

640950775 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1114730 (or 1114725 counting only the distinct ones).

The product of its (nonzero) digits is 264600, while the sum is 43.

The square root of 640950775 is about 25317.0056483779. The cubic root of 640950775 is about 862.2004112480.

The spelling of 640950775 in words is "six hundred forty million, nine hundred fifty thousand, seven hundred seventy-five".