645863324 has 24 divisors (see below), whose sum is σ = 1177470000. Its totient is φ = 309710720.

The previous prime is 645863291. The next prime is 645863329. The reversal of 645863324 is 423368546.

It is a Harshad number since it is a multiple of its sum of digits (41).

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (645863329) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 23699 + ... + 43050.

It is an arithmetic number, because the mean of its divisors is an integer number (49061250).

Almost surely, 2^645863324 is an apocalyptic number.

It is an amenable number.

645863324 is a deficient number, since it is larger than the sum of its proper divisors (531606676).

645863324 is a wasteful number, since it uses less digits than its factorization.

645863324 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 66853 (or 66851 counting only the distinct ones).

The product of its digits is 414720, while the sum is 41.

The square root of 645863324 is about 25413.8411893991. The cubic root of 645863324 is about 864.3975775825.

The spelling of 645863324 in words is "six hundred forty-five million, eight hundred sixty-three thousand, three hundred twenty-four".