645354244 has 6 divisors (see below), whose sum is σ = 1129369934. Its totient is φ = 322677120.

The previous prime is 645354211. The next prime is 645354271. The reversal of 645354244 is 442453546.

It can be written as a sum of positive squares in only one way, i.e., 641102400 + 4251844 = 25320^2 + 2062^2 .

It is an unprimeable number.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 80669277 + ... + 80669284.

Almost surely, 2^645354244 is an apocalyptic number.

It is an amenable number.

645354244 is a deficient number, since it is larger than the sum of its proper divisors (484015690).

645354244 is a wasteful number, since it uses less digits than its factorization.

645354244 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 161338565 (or 161338563 counting only the distinct ones).

The product of its digits is 230400, while the sum is 37.

The square root of 645354244 is about 25403.8234130219. The cubic root of 645354244 is about 864.1704071319.

The spelling of 645354244 in words is "six hundred forty-five million, three hundred fifty-four thousand, two hundred forty-four".