65121439 has 2 divisors, whose sum is σ = 65121440. Its totient is φ = 65121438.

The previous prime is 65121437. The next prime is 65121449. The reversal of 65121439 is 93412156.

It is a weak prime.

It is a cyclic number.

It is not a de Polignac number, because 65121439 - 2¹ = 65121437 is a prime.

Together with 65121437, it forms a pair of twin primes.

It is a self number, because there is not a number n which added to its sum of digits gives 65121439.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (65121431) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 32560719 + 32560720.

It is an arithmetic number, because the mean of its divisors is an integer number (32560720).

Almost surely, 2^65121439 is an apocalyptic number.

65121439 is a deficient number, since it is larger than the sum of its proper divisors (1).

65121439 is an equidigital number, since it uses as much as digits as its factorization.

65121439 is an evil number, because the sum of its binary digits is even.

The product of its digits is 6480, while the sum is 31.

The square root of 65121439 is about 8069.7855609675. The cubic root of 65121439 is about 402.3228164496.

The spelling of 65121439 in words is "sixty-five million, one hundred twenty-one thousand, four hundred thirty-nine".