621776261 has 2 divisors, whose sum is σ = 621776262. Its totient is φ = 621776260.

The previous prime is 621776249. The next prime is 621776293. The reversal of 621776261 is 162677126.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 493950625 + 127825636 = 22225^2 + 11306^2 .

It is a cyclic number.

It is not a de Polignac number, because 621776261 - 2²² = 617581957 is a prime.

It is a Chen prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (621773261) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 310888130 + 310888131.

It is an arithmetic number, because the mean of its divisors is an integer number (310888131).

Almost surely, 2^621776261 is an apocalyptic number.

It is an amenable number.

621776261 is a deficient number, since it is larger than the sum of its proper divisors (1).

621776261 is an equidigital number, since it uses as much as digits as its factorization.

621776261 is an evil number, because the sum of its binary digits is even.

The product of its digits is 42336, while the sum is 38.

The square root of 621776261 is about 24935.4418649440. The cubic root of 621776261 is about 853.5154343459.

The spelling of 621776261 in words is "six hundred twenty-one million, seven hundred seventy-six thousand, two hundred sixty-one".