640037972 has 48 divisors (see below), whose sum is σ = 1322133120. Its totient is φ = 265410432.

The previous prime is 640037927. The next prime is 640038001. The reversal of 640037972 is 279730046.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 128798 + ... + 133674.

It is an arithmetic number, because the mean of its divisors is an integer number (27544440).

Almost surely, 2^640037972 is an apocalyptic number.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 640037972, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (661066560).

640037972 is an abundant number, since it is smaller than the sum of its proper divisors (682095148).

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

640037972 is a wasteful number, since it uses less digits than its factorization.

640037972 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 5040 (or 5038 counting only the distinct ones).

The product of its (nonzero) digits is 63504, while the sum is 38.

The square root of 640037972 is about 25298.9717577612. The cubic root of 640037972 is about 861.7909190495.

The spelling of 640037972 in words is "six hundred forty million, thirty-seven thousand, nine hundred seventy-two".