64990657 has 2 divisors, whose sum is σ = 64990658. Its totient is φ = 64990656.

The previous prime is 64990591. The next prime is 64990661. The reversal of 64990657 is 75609946.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 53129521 + 11861136 = 7289^2 + 3444^2 .

It is a cyclic number.

It is not a de Polignac number, because 64990657 - 2⁷ = 64990529 is a prime.

It is not a weakly prime, because it can be changed into another prime (64990357) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 32495328 + 32495329.

It is an arithmetic number, because the mean of its divisors is an integer number (32495329).

Almost surely, 2^64990657 is an apocalyptic number.

It is an amenable number.

64990657 is a deficient number, since it is larger than the sum of its proper divisors (1).

64990657 is an equidigital number, since it uses as much as digits as its factorization.

64990657 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 408240, while the sum is 46.

The square root of 64990657 is about 8061.6782992129. The cubic root of 64990657 is about 402.0533105047.

The spelling of 64990657 in words is "sixty-four million, nine hundred ninety thousand, six hundred fifty-seven".