640144332 has 36 divisors (see below), whose sum is σ = 1620889816. Its totient is φ = 213019200.

The previous prime is 640144319. The next prime is 640144343. The reversal of 640144332 is 233441046.

640144332 is a `hidden beast` number, since 640 + 14 + 4 + 3 + 3 + 2 = 666.

It is a tau number, because it is divible by the number of its divisors (36).

It is a junction number, because it is equal to n+sod(n) for n = 640144296 and 640144305.

It is an unprimeable number.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 6843 + ... + 36429.

Almost surely, 2^640144332 is an apocalyptic number.

It is an amenable number.

640144332 is an abundant number, since it is smaller than the sum of its proper divisors (980745484).

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

640144332 is a wasteful number, since it uses less digits than its factorization.

640144332 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 30198 (or 30193 counting only the distinct ones).

The product of its (nonzero) digits is 6912, while the sum is 27.

The square root of 640144332 is about 25301.0737321561. The cubic root of 640144332 is about 861.8386531993.

Adding to 640144332 its reverse (233441046), we get a palindrome (873585378).

The spelling of 640144332 in words is "six hundred forty million, one hundred forty-four thousand, three hundred thirty-two".