645353272 has 8 divisors (see below), whose sum is σ = 1210037400. Its totient is φ = 322676632.

The previous prime is 645353263. The next prime is 645353299. The reversal of 645353272 is 272353546.

It is a tau number, because it is divible by the number of its divisors (8).

It is a super-2 number, since 2×645353272² = 832961691362211968, which contains 22 as substring.

It is a congruent number.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 40334572 + ... + 40334587.

It is an arithmetic number, because the mean of its divisors is an integer number (151254675).

Almost surely, 2^645353272 is an apocalyptic number.

It is an amenable number.

645353272 is a deficient number, since it is larger than the sum of its proper divisors (564684128).

645353272 is a wasteful number, since it uses less digits than its factorization.

645353272 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 80669165 (or 80669161 counting only the distinct ones).

The product of its digits is 151200, while the sum is 37.

The square root of 645353272 is about 25403.8042820362. The cubic root of 645353272 is about 864.1699732751.

The spelling of 645353272 in words is "six hundred forty-five million, three hundred fifty-three thousand, two hundred seventy-two".