65981761 has 2 divisors, whose sum is σ = 65981762. Its totient is φ = 65981760.

The previous prime is 65981759. The next prime is 65981789. The reversal of 65981761 is 16718956.

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., 43362225 + 22619536 = 6585^2 + 4756^2 .

It is a cyclic number.

It is not a de Polignac number, because 65981761 - 2¹ = 65981759 is a prime.

It is a super-2 number, since 2×65981761² = 8707185569322242, which contains 22 as substring.

Together with 65981759, it forms a pair of twin primes.

It is not a weakly prime, because it can be changed into another prime (65981731) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 32990880 + 32990881.

It is an arithmetic number, because the mean of its divisors is an integer number (32990881).

Almost surely, 2^65981761 is an apocalyptic number.

It is an amenable number.

65981761 is a deficient number, since it is larger than the sum of its proper divisors (1).

65981761 is an equidigital number, since it uses as much as digits as its factorization.

65981761 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 90720, while the sum is 43.

The square root of 65981761 is about 8122.9157942207. The cubic root of 65981761 is about 404.0867722807.

The spelling of 65981761 in words is "sixty-five million, nine hundred eighty-one thousand, seven hundred sixty-one".