646400724400 has 30 divisors (see below), whose sum is σ = 1552977741332. Its totient is φ = 258560289600.

The previous prime is 646400724397. The next prime is 646400724419. The reversal of 646400724400 is 4427004646.

It is a self number, because there is not a number n which added to its sum of digits gives 646400724400.

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 in 5 ways as a sum of consecutive naturals, for example, 808000506 + ... + 808001305.

Almost surely, 2^646400724400 is an apocalyptic number.

It is an amenable number.

646400724400 is an abundant number, since it is smaller than the sum of its proper divisors (906577016932).

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

646400724400 is a wasteful number, since it uses less digits than its factorization.

646400724400 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1616001829 (or 1616001818 counting only the distinct ones).

The product of its (nonzero) digits is 129024, while the sum is 37.

The spelling of 646400724400 in words is "six hundred forty-six billion, four hundred million, seven hundred twenty-four thousand, four hundred".