621043964640 has 768 divisors, whose sum is σ = 2542009236480. Its totient is φ = 141684940800.

The previous prime is 621043964633. The next prime is 621043964659. The reversal of 621043964640 is 46469340126.

621043964640 is a `hidden beast` number, since 6 + 210 + 4 + 396 + 4 + 6 + 40 = 666.

It is a Harshad number since it is a multiple of its sum of digits (45).

It is a congruent number.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 127 ways as a sum of consecutive naturals, for example, 65430295 + ... + 65439785.

It is an arithmetic number, because the mean of its divisors is an integer number (3309907860).

Almost surely, 2^621043964640 is an apocalyptic number.

621043964640 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 621043964640, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (1271004618240).

621043964640 is an abundant number, since it is smaller than the sum of its proper divisors (1920965271840).

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

621043964640 is a wasteful number, since it uses less digits than its factorization.

621043964640 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 9555 (or 9529 counting only the distinct ones).

The product of its (nonzero) digits is 746496, while the sum is 45.

The spelling of 621043964640 in words is "six hundred twenty-one billion, forty-three million, nine hundred sixty-four thousand, six hundred forty".