65681977 has 2 divisors, whose sum is σ = 65681978. Its totient is φ = 65681976.

The previous prime is 65681947. The next prime is 65682007. The reversal of 65681977 is 77918656.

It is a balanced prime because it is at equal distance from previous prime (65681947) and next prime (65682007).

It can be written as a sum of positive squares in only one way, i.e., 47114496 + 18567481 = 6864^2 + 4309^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-65681977 is a prime.

It is a self number, because there is not a number n which added to its sum of digits gives 65681977.

It is not a weakly prime, because it can be changed into another prime (65681947) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 32840988 + 32840989.

It is an arithmetic number, because the mean of its divisors is an integer number (32840989).

Almost surely, 2^65681977 is an apocalyptic number.

It is an amenable number.

65681977 is a deficient number, since it is larger than the sum of its proper divisors (1).

65681977 is an equidigital number, since it uses as much as digits as its factorization.

65681977 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 635040, while the sum is 49.

The square root of 65681977 is about 8104.4418068119. The cubic root of 65681977 is about 403.4738621183.

The spelling of 65681977 in words is "sixty-five million, six hundred eighty-one thousand, nine hundred seventy-seven".