645516813290 has 32 divisors (see below), whose sum is σ = 1172673040896. Its totient is φ = 255830420160.

The previous prime is 645516813247. The next prime is 645516813353. The reversal of 645516813290 is 92318615546.

It is a Smith number, since the sum of its digits (50) coincides with the sum of the digits of its prime factors. Since it is squarefree, it is also a hoax 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, 215417 + ... + 1156476.

It is an arithmetic number, because the mean of its divisors is an integer number (36646032528).

Almost surely, 2^645516813290 is an apocalyptic number.

645516813290 is a deficient number, since it is larger than the sum of its proper divisors (527156227606).

645516813290 is a wasteful number, since it uses less digits than its factorization.

645516813290 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1372334.

The product of its (nonzero) digits is 1555200, while the sum is 50.

The spelling of 645516813290 in words is "six hundred forty-five billion, five hundred sixteen million, eight hundred thirteen thousand, two hundred ninety".