640213332 has 24 divisors (see below), whose sum is σ = 1629634272. Its totient is φ = 194004000.

The previous prime is 640213297. The next prime is 640213339. The reversal of 640213332 is 233312046.

It is a super-2 number, since 2×640213332² = 819746220941084448, which contains 22 as substring.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (640213339) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 2424919 + ... + 2425182.

It is an arithmetic number, because the mean of its divisors is an integer number (67901428).

Almost surely, 2^640213332 is an apocalyptic number.

It is an amenable number.

640213332 is an abundant number, since it is smaller than the sum of its proper divisors (989420940).

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

640213332 is a wasteful number, since it uses less digits than its factorization.

640213332 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 4850119 (or 4850117 counting only the distinct ones).

The product of its (nonzero) digits is 2592, while the sum is 24.

The square root of 640213332 is about 25302.4372739070. The cubic root of 640213332 is about 861.8696174301.

Adding to 640213332 its reverse (233312046), we get a palindrome (873525378).

The spelling of 640213332 in words is "six hundred forty million, two hundred thirteen thousand, three hundred thirty-two".