621331812864 has 240 divisors, whose sum is σ = 2082980877120. Its totient is φ = 174612602880.

The previous prime is 621331812823. The next prime is 621331812869. The reversal of 621331812864 is 468218133126.

621331812864 is a `hidden beast` number, since 62 + 133 + 181 + 286 + 4 = 666.

It is a nude number because it is divisible by every one of its digits.

It is not an unprimeable number, because it can be changed into a prime (621331812869) by changing a digit.

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 23 ways as a sum of consecutive naturals, for example, 1809727 + ... + 2125505.

It is an arithmetic number, because the mean of its divisors is an integer number (8679086988).

Almost surely, 2^621331812864 is an apocalyptic number.

621331812864 is a gapful number since it is divisible by the number (64) 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 621331812864, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (1041490438560).

621331812864 is an abundant number, since it is smaller than the sum of its proper divisors (1461649064256).

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

621331812864 is a wasteful number, since it uses less digits than its factorization.

621331812864 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 315871 (or 315852 counting only the distinct ones).

The product of its digits is 331776, while the sum is 45.

The spelling of 621331812864 in words is "six hundred twenty-one billion, three hundred thirty-one million, eight hundred twelve thousand, eight hundred sixty-four".