640745952 has 384 divisors, whose sum is σ = 2249856000. Its totient is φ = 158054400.

The previous prime is 640745951. The next prime is 640745957. The reversal of 640745952 is 259547046.

It is a Harshad number since it is a multiple of its sum of digits (42).

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (640745951) by changing a digit.

It is a polite number, since it can be written in 63 ways as a sum of consecutive naturals, for example, 10504002 + ... + 10504062.

It is an arithmetic number, because the mean of its divisors is an integer number (5859000).

Almost surely, 2^640745952 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 640745952, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (1124928000).

640745952 is an abundant number, since it is smaller than the sum of its proper divisors (1609110048).

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

640745952 is a wasteful number, since it uses less digits than its factorization.

640745952 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 135 (or 113 counting only the distinct ones).

The product of its (nonzero) digits is 302400, while the sum is 42.

The square root of 640745952 is about 25312.9601587803. The cubic root of 640745952 is about 862.1085595300.

The spelling of 640745952 in words is "six hundred forty million, seven hundred forty-five thousand, nine hundred fifty-two".