621993456 has 180 divisors, whose sum is σ = 2038722192. Its totient is φ = 177020928.

The previous prime is 621993403. The next prime is 621993473. The reversal of 621993456 is 654399126.

621993456 is a `hidden beast` number, since 6 + 2 + 199 + 3 + 456 = 666.

621993456 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 35 ways as a sum of consecutive naturals, for example, 2420080 + ... + 2420336.

Almost surely, 2^621993456 is an apocalyptic number.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 621993456, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (1019361096).

621993456 is an abundant number, since it is smaller than the sum of its proper divisors (1416728736).

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

621993456 is an equidigital number, since it uses as much as digits as its factorization.

621993456 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 306 (or 269 counting only the distinct ones).

The product of its digits is 349920, while the sum is 45.

The square root of 621993456 is about 24939.7966310874. The cubic root of 621993456 is about 853.6148043366.

The spelling of 621993456 in words is "six hundred twenty-one million, nine hundred ninety-three thousand, four hundred fifty-six".