644475362 has 16 divisors (see below), whose sum is σ = 982179000. Its totient is φ = 317122560.

The previous prime is 644475353. The next prime is 644475373. The reversal of 644475362 is 263574446.

It can be written as a sum of positive squares in 4 ways, for example, as 276257641 + 368217721 = 16621^2 + 19189^2 .

It is an unprimeable number.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 22562 + ... + 42402.

Almost surely, 2^644475362 is an apocalyptic number.

644475362 is a deficient number, since it is larger than the sum of its proper divisors (337703638).

644475362 is a wasteful number, since it uses less digits than its factorization.

644475362 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 20101.

The product of its digits is 483840, while the sum is 41.

The square root of 644475362 is about 25386.5192966661. The cubic root of 644475362 is about 863.7779359358. Note that the first 3 decimals are identical.

The spelling of 644475362 in words is "six hundred forty-four million, four hundred seventy-five thousand, three hundred sixty-two".