640807452 has 72 divisors (see below), whose sum is σ = 1805403600. Its totient is φ = 190453248.

The previous prime is 640807441. The next prime is 640807459. The reversal of 640807452 is 254708046.

640807452 is a `hidden beast` number, since 640 + 8 + 0 + 7 + 4 + 5 + 2 = 666.

It is a Harshad number since it is a multiple of its sum of digits (36).

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (640807459) by changing a digit.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 15927 + ... + 39182.

It is an arithmetic number, because the mean of its divisors is an integer number (25075050).

Almost surely, 2^640807452 is an apocalyptic number.

It is an amenable number.

640807452 is an abundant number, since it is smaller than the sum of its proper divisors (1164596148).

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

640807452 is a wasteful number, since it uses less digits than its factorization.

640807452 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 55155 (or 55150 counting only the distinct ones).

The product of its (nonzero) digits is 53760, while the sum is 36.

The square root of 640807452 is about 25314.1749223632. The cubic root of 640807452 is about 862.1361409139.

The spelling of 640807452 in words is "six hundred forty million, eight hundred seven thousand, four hundred fifty-two".