640474244 has 12 divisors (see below), whose sum is σ = 1136616768. Its totient is φ = 315726600.

The previous prime is 640474147. The next prime is 640474277. The reversal of 640474244 is 442474046.

It is a hoax number, since the sum of its digits (35) coincides with the sum of the digits of its distinct prime factors.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 1127312 + ... + 1127879.

It is an arithmetic number, because the mean of its divisors is an integer number (94718064).

Almost surely, 2^640474244 is an apocalyptic number.

It is an amenable number.

640474244 is a deficient number, since it is larger than the sum of its proper divisors (496142524).

640474244 is a wasteful number, since it uses less digits than its factorization.

640474244 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 2255266 (or 2255264 counting only the distinct ones).

The product of its (nonzero) digits is 86016, while the sum is 35.

The square root of 640474244 is about 25307.5926156559. The cubic root of 640474244 is about 861.9866834003.

The spelling of 640474244 in words is "six hundred forty million, four hundred seventy-four thousand, two hundred forty-four".