65915891 has 2 divisors, whose sum is σ = 65915892. Its totient is φ = 65915890.

The previous prime is 65915887. The next prime is 65915893. The reversal of 65915891 is 19851956.

It is a strong prime.

It is a cyclic number.

It is not a de Polignac number, because 65915891 - 2² = 65915887 is a prime.

Together with 65915893, 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 (65915893) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 32957945 + 32957946.

It is an arithmetic number, because the mean of its divisors is an integer number (32957946).

Almost surely, 2^65915891 is an apocalyptic number.

65915891 is a deficient number, since it is larger than the sum of its proper divisors (1).

65915891 is an equidigital number, since it uses as much as digits as its factorization.

65915891 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 97200, while the sum is 44.

The square root of 65915891 is about 8118.8602032551. The cubic root of 65915891 is about 403.9522600681.

The spelling of 65915891 in words is "sixty-five million, nine hundred fifteen thousand, eight hundred ninety-one".