646721441053400 has 48 divisors (see below), whose sum is σ = 1504089864219240. Its totient is φ = 258609004160000.

The previous prime is 646721441053349. The next prime is 646721441053423. The reversal of 646721441053400 is 4350144127646.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 496674809 + ... + 497975208.

Almost surely, 2^{646721441053400} is an apocalyptic number.

It is an amenable number.

646721441053400 is an abundant number, since it is smaller than the sum of its proper divisors (857368423165840).

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

646721441053400 is a wasteful number, since it uses less digits than its factorization.

646721441053400 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 994653284 (or 994653275 counting only the distinct ones).

The product of its (nonzero) digits is 1935360, while the sum is 47.

The spelling of 646721441053400 in words is "six hundred forty-six trillion, seven hundred twenty-one billion, four hundred forty-one million, fifty-three thousand, four hundred".