656440249 has 2 divisors, whose sum is σ = 656440250. Its totient is φ = 656440248.

The previous prime is 656440247. The next prime is 656440297. The reversal of 656440249 is 942044656.

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., 590830249 + 65610000 = 24307^2 + 8100^2 .

It is a cyclic number.

It is not a de Polignac number, because 656440249 - 2¹ = 656440247 is a prime.

Together with 656440247, it forms a pair of twin primes.

It is a Chen prime.

It is not a weakly prime, because it can be changed into another prime (656440243) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 328220124 + 328220125.

It is an arithmetic number, because the mean of its divisors is an integer number (328220125).

Almost surely, 2^656440249 is an apocalyptic number.

It is an amenable number.

656440249 is a deficient number, since it is larger than the sum of its proper divisors (1).

656440249 is an equidigital number, since it uses as much as digits as its factorization.

656440249 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 207360, while the sum is 40.

The square root of 656440249 is about 25621.0899260746. The cubic root of 656440249 is about 869.0906290563.

The spelling of 656440249 in words is "six hundred fifty-six million, four hundred forty thousand, two hundred forty-nine".