626561326661 has 2 divisors, whose sum is σ = 626561326662. Its totient is φ = 626561326660.

The previous prime is 626561326603. The next prime is 626561326759. The reversal of 626561326661 is 166623165626.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 594772576225 + 31788750436 = 771215^2 + 178294^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-626561326661 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (626561329661) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 313280663330 + 313280663331.

It is an arithmetic number, because the mean of its divisors is an integer number (313280663331).

Almost surely, 2^626561326661 is an apocalyptic number.

It is an amenable number.

626561326661 is a deficient number, since it is larger than the sum of its proper divisors (1).

626561326661 is an equidigital number, since it uses as much as digits as its factorization.

626561326661 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 2799360, while the sum is 50.

The spelling of 626561326661 in words is "six hundred twenty-six billion, five hundred sixty-one million, three hundred twenty-six thousand, six hundred sixty-one".