640446521416 has 64 divisors (see below), whose sum is σ = 1296859964400. Its totient is φ = 294757429248.

The previous prime is 640446521381. The next prime is 640446521419. The reversal of 640446521416 is 614125644046.

It is a happy number.

It can be written as a sum of positive squares in 8 ways, for example, as 356086692900 + 284359828516 = 596730^2 + 533254^2 .

It is not an unprimeable number, because it can be changed into a prime (640446521419) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 61123570 + ... + 61134046.

Almost surely, 2^640446521416 is an apocalyptic number.

It is an amenable number.

640446521416 is an abundant number, since it is smaller than the sum of its proper divisors (656413442984).

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

640446521416 is a wasteful number, since it uses less digits than its factorization.

640446521416 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 12098 (or 12094 counting only the distinct ones).

The product of its (nonzero) digits is 552960, while the sum is 43.

The spelling of 640446521416 in words is "six hundred forty billion, four hundred forty-six million, five hundred twenty-one thousand, four hundred sixteen".