645323240784 has 40 divisors (see below), whose sum is σ = 1739566999872. Its totient is φ = 205755235840.

The previous prime is 645323240647. The next prime is 645323240833. The reversal of 645323240784 is 487042323546.

It is a hoax number, since the sum of its digits (48) coincides with the sum of the digits of its distinct prime factors.

It is a Harshad number since it is a multiple of its sum of digits (48).

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 292264857 + ... + 292267064.

Almost surely, 2^645323240784 is an apocalyptic number.

It is an amenable number.

645323240784 is an abundant number, since it is smaller than the sum of its proper divisors (1094243759088).

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

645323240784 is a wasteful number, since it uses less digits than its factorization.

645323240784 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 584531955 (or 584531949 counting only the distinct ones).

The product of its (nonzero) digits is 3870720, while the sum is 48.

The spelling of 645323240784 in words is "six hundred forty-five billion, three hundred twenty-three million, two hundred forty thousand, seven hundred eighty-four".