65681657 has 2 divisors, whose sum is σ = 65681658. Its totient is φ = 65681656.

The previous prime is 65681639. The next prime is 65681669. The reversal of 65681657 is 75618656.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 58690921 + 6990736 = 7661^2 + 2644^2 .

It is a cyclic number.

It is not a de Polignac number, because 65681657 - 2⁶ = 65681593 is a prime.

It is equal to p_3878396 and since 65681657 and 3878396 have the same sum of digits, it is a Honaker prime.

It is not a weakly prime, because it can be changed into another prime (65681617) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 32840828 + 32840829.

It is an arithmetic number, because the mean of its divisors is an integer number (32840829).

Almost surely, 2^65681657 is an apocalyptic number.

It is an amenable number.

65681657 is a deficient number, since it is larger than the sum of its proper divisors (1).

65681657 is an equidigital number, since it uses as much as digits as its factorization.

65681657 is an evil number, because the sum of its binary digits is even.

The product of its digits is 302400, while the sum is 44.

The square root of 65681657 is about 8104.4220645275. The cubic root of 65681657 is about 403.4732068810.

The spelling of 65681657 in words is "sixty-five million, six hundred eighty-one thousand, six hundred fifty-seven".