656891489 has 2 divisors, whose sum is σ = 656891490. Its totient is φ = 656891488.

The previous prime is 656891483. The next prime is 656891513. The reversal of 656891489 is 984198656.

It is a happy number.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 416486464 + 240405025 = 20408^2 + 15505^2 .

It is a cyclic number.

It is not a de Polignac number, because 656891489 - 2⁸ = 656891233 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 (656891483) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 328445744 + 328445745.

It is an arithmetic number, because the mean of its divisors is an integer number (328445745).

Almost surely, 2^656891489 is an apocalyptic number.

It is an amenable number.

656891489 is a deficient number, since it is larger than the sum of its proper divisors (1).

656891489 is an equidigital number, since it uses as much as digits as its factorization.

656891489 is an evil number, because the sum of its binary digits is even.

The product of its digits is 3732480, while the sum is 56.

The square root of 656891489 is about 25629.8944398919. The cubic root of 656891489 is about 869.2897223888.

The spelling of 656891489 in words is "six hundred fifty-six million, eight hundred ninety-one thousand, four hundred eighty-nine".