640012535 has 8 divisors (see below), whose sum is σ = 778536240. Its totient is φ = 504995904.

The previous prime is 640012517. The next prime is 640012543. The reversal of 640012535 is 535210046.

It is a sphenic number, since it is the product of 3 distinct primes.

It is a cyclic number.

It is not a de Polignac number, because 640012535 - 2⁸ = 640012279 is a prime.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 876365 + ... + 877094.

It is an arithmetic number, because the mean of its divisors is an integer number (97317030).

Almost surely, 2^640012535 is an apocalyptic number.

640012535 is a deficient number, since it is larger than the sum of its proper divisors (138523705).

640012535 is a wasteful number, since it uses less digits than its factorization.

640012535 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1753537.

The product of its (nonzero) digits is 3600, while the sum is 26.

The square root of 640012535 is about 25298.4690248244. The cubic root of 640012535 is about 861.7795021924.

The spelling of 640012535 in words is "six hundred forty million, twelve thousand, five hundred thirty-five".