665032631363561 has 2 divisors, whose sum is σ = 665032631363562. Its totient is φ = 665032631363560.

The previous prime is 665032631363479. The next prime is 665032631363563. The reversal of 665032631363561 is 165363136230566.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 627715743713536 + 37316887650025 = 25054256^2 + 6108755^2 .

It is a cyclic number.

It is not a de Polignac number, because 665032631363561 - 2²² = 665032627169257 is a prime.

Together with 665032631363563, it forms a pair of twin primes.

It is a Chen prime.

It is a junction number, because it is equal to n+sod(n) for n = 665032631363497 and 665032631363506.

It is not a weakly prime, because it can be changed into another prime (665032631363563) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 332516315681780 + 332516315681781.

It is an arithmetic number, because the mean of its divisors is an integer number (332516315681781).

Almost surely, 2^{665032631363561} is an apocalyptic number.

It is an amenable number.

665032631363561 is a deficient number, since it is larger than the sum of its proper divisors (1).

665032631363561 is an equidigital number, since it uses as much as digits as its factorization.

665032631363561 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 31492800, while the sum is 56.

The spelling of 665032631363561 in words is "six hundred sixty-five trillion, thirty-two billion, six hundred thirty-one million, three hundred sixty-three thousand, five hundred sixty-one".