645516446404 has 12 divisors (see below), whose sum is σ = 1129664362428. Its totient is φ = 322755200000.

The previous prime is 645516446347. The next prime is 645516446413. The reversal of 645516446404 is 404644615546.

It is a happy number.

It can be written as a sum of positive squares in 2 ways, for example, as 638004757504 + 7511688900 = 798752^2 + 86670^2 .

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 235597 + ... + 1160404.

It is an arithmetic number, because the mean of its divisors is an integer number (94138696869).

Almost surely, 2^645516446404 is an apocalyptic number.

It is an amenable number.

645516446404 is a deficient number, since it is larger than the sum of its proper divisors (484147916024).

645516446404 is a wasteful number, since it uses less digits than its factorization.

645516446404 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1511606 (or 1511604 counting only the distinct ones).

The product of its (nonzero) digits is 5529600, while the sum is 49.

The spelling of 645516446404 in words is "six hundred forty-five billion, five hundred sixteen million, four hundred forty-six thousand, four hundred four".