6626989661 has 2 divisors, whose sum is σ = 6626989662. Its totient is φ = 6626989660.

The previous prime is 6626989639. The next prime is 6626989669. The reversal of 6626989661 is 1669896266.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 4312417561 + 2314572100 = 65669^2 + 48110^2 .

It is a cyclic number.

It is not a de Polignac number, because 6626989661 - 2²² = 6622795357 is a prime.

It is a self number, because there is not a number n which added to its sum of digits gives 6626989661.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (6626989669) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 3313494830 + 3313494831.

It is an arithmetic number, because the mean of its divisors is an integer number (3313494831).

Almost surely, 2^6626989661 is an apocalyptic number.

It is an amenable number.

6626989661 is a deficient number, since it is larger than the sum of its proper divisors (1).

6626989661 is an equidigital number, since it uses as much as digits as its factorization.

6626989661 is an evil number, because the sum of its binary digits is even.

The product of its digits is 10077696, while the sum is 59.

The square root of 6626989661 is about 81406.3244533249. The cubic root of 6626989661 is about 1878.3308767887.

The spelling of 6626989661 in words is "six billion, six hundred twenty-six million, nine hundred eighty-nine thousand, six hundred sixty-one".