645727344 has 40 divisors (see below), whose sum is σ = 1677792912. Its totient is φ = 213995520.

The previous prime is 645727343. The next prime is 645727349. The reversal of 645727344 is 443727546.

It is a junction number, because it is equal to n+sod(n) for n = 645727296 and 645727305.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (645727343) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 30577 + ... + 47184.

Almost surely, 2^645727344 is an apocalyptic number.

It is an amenable number.

645727344 is an abundant number, since it is smaller than the sum of its proper divisors (1032065568).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

645727344 is a wasteful number, since it uses less digits than its factorization.

645727344 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 77945 (or 77939 counting only the distinct ones).

The product of its digits is 564480, while the sum is 42.

The square root of 645727344 is about 25411.1657347710. The cubic root of 645727344 is about 864.3369099313.

The spelling of 645727344 in words is "six hundred forty-five million, seven hundred twenty-seven thousand, three hundred forty-four".