661464833 has 2 divisors, whose sum is σ = 661464834. Its totient is φ = 661464832.

The previous prime is 661464779. The next prime is 661464877. The reversal of 661464833 is 338464166.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 633881329 + 27583504 = 25177^2 + 5252^2 .

It is a cyclic number.

It is not a de Polignac number, because 661464833 - 2²⁰ = 660416257 is a prime.

It is a Sophie Germain prime.

It is a Chen prime.

It is a Curzon number.

It is not a weakly prime, because it can be changed into another prime (661404833) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 330732416 + 330732417.

It is an arithmetic number, because the mean of its divisors is an integer number (330732417).

Almost surely, 2^661464833 is an apocalyptic number.

It is an amenable number.

661464833 is a deficient number, since it is larger than the sum of its proper divisors (1).

661464833 is an equidigital number, since it uses as much as digits as its factorization.

661464833 is an evil number, because the sum of its binary digits is even.

The product of its digits is 248832, while the sum is 41.

The square root of 661464833 is about 25718.9586297735. The cubic root of 661464833 is about 871.3024192796.

The spelling of 661464833 in words is "six hundred sixty-one million, four hundred sixty-four thousand, eight hundred thirty-three".