645545313 has 12 divisors (see below), whose sum is σ = 1065662208. Its totient is φ = 368883000.

The previous prime is 645545309. The next prime is 645545317. The reversal of 645545313 is 313545546.

645545313 is a `hidden beast` number, since 645 + 5 + 4 + 5 + 3 + 1 + 3 = 666.

It is an interprime number because it is at equal distance from previous prime (645545309) and next prime (645545317).

It is not a de Polignac number, because 645545313 - 2² = 645545309 is a prime.

It is a super-2 number, since 2×645545313² = 833457502272535938, which contains 22 as substring.

It is a hoax number, since the sum of its digits (36) coincides with the sum of the digits of its distinct prime factors.

It is not an unprimeable number, because it can be changed into a prime (645545317) by changing a digit.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 5123313 + ... + 5123438.

It is an arithmetic number, because the mean of its divisors is an integer number (88805184).

Almost surely, 2^645545313 is an apocalyptic number.

645545313 is a gapful number since it is divisible by the number (63) formed by its first and last digit.

It is an amenable number.

645545313 is a deficient number, since it is larger than the sum of its proper divisors (420116895).

645545313 is a wasteful number, since it uses less digits than its factorization.

645545313 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 10246764 (or 10246761 counting only the distinct ones).

The product of its digits is 108000, while the sum is 36.

The square root of 645545313 is about 25407.5837694181. The cubic root of 645545313 is about 864.2556832339.

The spelling of 645545313 in words is "six hundred forty-five million, five hundred forty-five thousand, three hundred thirteen".