649612961 has 2 divisors, whose sum is σ = 649612962. Its totient is φ = 649612960.

The previous prime is 649612939. The next prime is 649612969. The reversal of 649612961 is 169216946.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 348382225 + 301230736 = 18665^2 + 17356^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-649612961 is a prime.

It is a Chen prime.

It is not a weakly prime, because it can be changed into another prime (649612969) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 324806480 + 324806481.

It is an arithmetic number, because the mean of its divisors is an integer number (324806481).

Almost surely, 2^649612961 is an apocalyptic number.

It is an amenable number.

649612961 is a deficient number, since it is larger than the sum of its proper divisors (1).

649612961 is an equidigital number, since it uses as much as digits as its factorization.

649612961 is an evil number, because the sum of its binary digits is even.

The product of its digits is 139968, while the sum is 44.

The square root of 649612961 is about 25487.5059784201. The cubic root of 649612961 is about 866.0671387339.

The spelling of 649612961 in words is "six hundred forty-nine million, six hundred twelve thousand, nine hundred sixty-one".