640461612 has 96 divisors (see below), whose sum is σ = 1770209280. Its totient is φ = 176362560.

The previous prime is 640461599. The next prime is 640461623. The reversal of 640461612 is 216164046.

It is a self number, because there is not a number n which added to its sum of digits gives 640461612.

It is an unprimeable number.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 1090783 + ... + 1091369.

It is an arithmetic number, because the mean of its divisors is an integer number (18439680).

Almost surely, 2^640461612 is an apocalyptic number.

640461612 is a gapful number since it is divisible by the number (62) formed by its first and last digit.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 640461612, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (885104640).

640461612 is an abundant number, since it is smaller than the sum of its proper divisors (1129747668).

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

640461612 is a wasteful number, since it uses less digits than its factorization.

640461612 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1051 (or 1049 counting only the distinct ones).

The product of its (nonzero) digits is 6912, while the sum is 30.

The square root of 640461612 is about 25307.3430450531. The cubic root of 640461612 is about 861.9810164082.

The spelling of 640461612 in words is "six hundred forty million, four hundred sixty-one thousand, six hundred twelve".