640191525 has 48 divisors (see below), whose sum is σ = 1146873024. Its totient is φ = 313850880.

The previous prime is 640191511. The next prime is 640191577. The reversal of 640191525 is 525191046.

It is not a de Polignac number, because 640191525 - 2⁷ = 640191397 is a prime.

It is a Curzon number.

It is a congruent number.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 47 ways as a sum of consecutive naturals, for example, 48987 + ... + 60663.

It is an arithmetic number, because the mean of its divisors is an integer number (23893188).

Almost surely, 2^640191525 is an apocalyptic number.

It is an amenable number.

640191525 is a deficient number, since it is larger than the sum of its proper divisors (506681499).

640191525 is a wasteful number, since it uses less digits than its factorization.

640191525 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 11750 (or 11745 counting only the distinct ones).

The product of its (nonzero) digits is 10800, while the sum is 33.

The square root of 640191525 is about 25302.0063433713. The cubic root of 640191525 is about 861.8598316274.

The spelling of 640191525 in words is "six hundred forty million, one hundred ninety-one thousand, five hundred twenty-five".