621421512461 has 2 divisors, whose sum is σ = 621421512462. Its totient is φ = 621421512460.

The previous prime is 621421512433. The next prime is 621421512469. The reversal of 621421512461 is 164215124126.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 620620962025 + 800550436 = 787795^2 + 28294^2 .

It is a cyclic number.

It is not a de Polignac number, because 621421512461 - 2²² = 621417318157 is a prime.

It is a super-2 number, since 2×621421512461² (a number of 24 digits) contains 22 as substring.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (621421512469) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 310710756230 + 310710756231.

It is an arithmetic number, because the mean of its divisors is an integer number (310710756231).

Almost surely, 2^621421512461 is an apocalyptic number.

It is an amenable number.

621421512461 is a deficient number, since it is larger than the sum of its proper divisors (1).

621421512461 is an equidigital number, since it uses as much as digits as its factorization.

621421512461 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 23040, while the sum is 35.

Adding to 621421512461 its reverse (164215124126), we get a palindrome (785636636587).

The spelling of 621421512461 in words is "six hundred twenty-one billion, four hundred twenty-one million, five hundred twelve thousand, four hundred sixty-one".