621308926621 has 2 divisors, whose sum is σ = 621308926622. Its totient is φ = 621308926620.

The previous prime is 621308926577. The next prime is 621308926643. The reversal of 621308926621 is 126629803126.

621308926621 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 333406927396 + 287901999225 = 577414^2 + 536565^2 .

It is a cyclic number.

It is not a de Polignac number, because 621308926621 - 2²⁵ = 621275372189 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (621308927621) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 310654463310 + 310654463311.

It is an arithmetic number, because the mean of its divisors is an integer number (310654463311).

Almost surely, 2^621308926621 is an apocalyptic number.

It is an amenable number.

621308926621 is a deficient number, since it is larger than the sum of its proper divisors (1).

621308926621 is an equidigital number, since it uses as much as digits as its factorization.

621308926621 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 373248, while the sum is 46.

The spelling of 621308926621 in words is "six hundred twenty-one billion, three hundred eight million, nine hundred twenty-six thousand, six hundred twenty-one".