646971494400 has 1560 divisors, whose sum is σ = 2990839984704. Its totient is φ = 134302924800.

The previous prime is 646971494371. The next prime is 646971494413. The reversal of 646971494400 is 4494179646.

646971494400 is a `hidden beast` number, since 6 + 4 + 6 + 97 + 149 + 4 + 400 = 666.

It is a super-2 number, since 2×646971494400² (a number of 24 digits) contains 22 as substring.

It is a Harshad number since it is a multiple of its sum of digits (54).

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 119 ways as a sum of consecutive naturals, for example, 638668294 + ... + 638669306.

Almost surely, 2^646971494400 is an apocalyptic number.

646971494400 is a gapful number since it is divisible by the number (60) formed by its first and last digit.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 646971494400, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (1495419992352).

646971494400 is an abundant number, since it is smaller than the sum of its proper divisors (2343868490304).

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

646971494400 is a wasteful number, since it uses less digits than its factorization.

646971494400 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1077 (or 1041 counting only the distinct ones).

The product of its (nonzero) digits is 5225472, while the sum is 54.

The spelling of 646971494400 in words is "six hundred forty-six billion, nine hundred seventy-one million, four hundred ninety-four thousand, four hundred".