621956761 has 2 divisors, whose sum is σ = 621956762. Its totient is φ = 621956760.

The previous prime is 621956729. The next prime is 621956821. The reversal of 621956761 is 167659126.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 491996761 + 129960000 = 22181^2 + 11400^2 .

It is a cyclic number.

It is not a de Polignac number, because 621956761 - 2⁵ = 621956729 is a prime.

It is a super-2 number, since 2×621956761² = 773660425107222242, which contains 22 as substring.

It is not a weakly prime, because it can be changed into another prime (621956161) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 310978380 + 310978381.

It is an arithmetic number, because the mean of its divisors is an integer number (310978381).

Almost surely, 2^621956761 is an apocalyptic number.

It is an amenable number.

621956761 is a deficient number, since it is larger than the sum of its proper divisors (1).

621956761 is an equidigital number, since it uses as much as digits as its factorization.

621956761 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 136080, while the sum is 43.

The square root of 621956761 is about 24939.0609486404. The cubic root of 621956761 is about 853.5980174444.

The spelling of 621956761 in words is "six hundred twenty-one million, nine hundred fifty-six thousand, seven hundred sixty-one".