621405253481 has 2 divisors, whose sum is σ = 621405253482. Its totient is φ = 621405253480.

The previous prime is 621405253477. The next prime is 621405253607. The reversal of 621405253481 is 184352504126.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 620772227881 + 633025600 = 787891^2 + 25160^2 .

It is a cyclic number.

It is not a de Polignac number, because 621405253481 - 2² = 621405253477 is a prime.

It is a super-2 number, since 2×621405253481² (a number of 24 digits) contains 22 as substring.

It is not a weakly prime, because it can be changed into another prime (621405253081) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 310702626740 + 310702626741.

It is an arithmetic number, because the mean of its divisors is an integer number (310702626741).

Almost surely, 2^621405253481 is an apocalyptic number.

It is an amenable number.

621405253481 is a deficient number, since it is larger than the sum of its proper divisors (1).

621405253481 is an equidigital number, since it uses as much as digits as its factorization.

621405253481 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 230400, while the sum is 41.

The spelling of 621405253481 in words is "six hundred twenty-one billion, four hundred five million, two hundred fifty-three thousand, four hundred eighty-one".