661047052961 has 2 divisors, whose sum is σ = 661047052962. Its totient is φ = 661047052960.

The previous prime is 661047052951. The next prime is 661047052969. The reversal of 661047052961 is 169250740166.

661047052961 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 660473163025 + 573889936 = 812695^2 + 23956^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-661047052961 is a prime.

It is a Sophie Germain prime.

It is a Curzon number.

It is not a weakly prime, because it can be changed into another prime (661047052969) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 330523526480 + 330523526481.

It is an arithmetic number, because the mean of its divisors is an integer number (330523526481).

Almost surely, 2^661047052961 is an apocalyptic number.

It is an amenable number.

661047052961 is a deficient number, since it is larger than the sum of its proper divisors (1).

661047052961 is an equidigital number, since it uses as much as digits as its factorization.

661047052961 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 544320, while the sum is 47.

The spelling of 661047052961 in words is "six hundred sixty-one billion, forty-seven million, fifty-two thousand, nine hundred sixty-one".