640535214 has 32 divisors (see below), whose sum is σ = 1479741696. Its totient is φ = 182683520.

The previous prime is 640535177. The next prime is 640535219. The reversal of 640535214 is 412535046.

It is a Curzon number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (640535219) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 284322 + ... + 286565.

It is an arithmetic number, because the mean of its divisors is an integer number (46241928).

Almost surely, 2^640535214 is an apocalyptic number.

640535214 is an abundant number, since it is smaller than the sum of its proper divisors (839206482).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

640535214 is a wasteful number, since it uses less digits than its factorization.

640535214 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 570920.

The product of its (nonzero) digits is 14400, while the sum is 30.

The square root of 640535214 is about 25308.7971662029. The cubic root of 640535214 is about 862.0140348309.

The spelling of 640535214 in words is "six hundred forty million, five hundred thirty-five thousand, two hundred fourteen".