640202444 has 18 divisors (see below), whose sum is σ = 1303269660. Its totient is φ = 274372392.

The previous prime is 640202443. The next prime is 640202461. The reversal of 640202444 is 444202046.

It is not an unprimeable number, because it can be changed into a prime (640202441) by changing a digit.

It is a polite number, since it can be written in 5 ways as a sum of consecutive naturals, for example, 1632974 + ... + 1633365.

It is an arithmetic number, because the mean of its divisors is an integer number (72403870).

Almost surely, 2^640202444 is an apocalyptic number.

It is an amenable number.

640202444 is an abundant number, since it is smaller than the sum of its proper divisors (663067216).

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

640202444 is a wasteful number, since it uses less digits than its factorization.

640202444 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 3266357 (or 3266348 counting only the distinct ones).

The product of its (nonzero) digits is 6144, while the sum is 26.

The square root of 640202444 is about 25302.2221158538. Note that the first 3 decimals coincide. The cubic root of 640202444 is about 861.8647315121.

The spelling of 640202444 in words is "six hundred forty million, two hundred two thousand, four hundred forty-four".