621443978882640 has 200 divisors, whose sum is σ = 2252209048645248. Its totient is φ = 158513246749440.

The previous prime is 621443978882621. The next prime is 621443978882647. The reversal of 621443978882640 is 46288879344126.

621443978882640 is a `hidden beast` number, since 6 + 2 + 1 + 4 + 439 + 78 + 8 + 82 + 6 + 40 = 666.

It is a super-2 number, since 2×621443978882640² (a number of 30 digits) contains 22 as substring.

It is a Harshad number since it is a multiple of its sum of digits (72).

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (621443978882647) by changing a digit.

It is a polite number, since it can be written in 39 ways as a sum of consecutive naturals, for example, 2084673756 + ... + 2084971835.

Almost surely, 2^{621443978882640} is an apocalyptic number.

621443978882640 is a gapful number since it is divisible by the number (60) formed by its first and last digit.

It is an amenable number.

621443978882640 is an abundant number, since it is smaller than the sum of its proper divisors (1630765069762608).

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

621443978882640 is a wasteful number, since it uses less digits than its factorization.

621443978882640 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 4169645639 (or 4169645624 counting only the distinct ones).

The product of its (nonzero) digits is 891813888, while the sum is 72.

The spelling of 621443978882640 in words is "six hundred twenty-one trillion, four hundred forty-three billion, nine hundred seventy-eight million, eight hundred eighty-two thousand, six hundred forty".