65139523 has 4 divisors (see below), whose sum is σ = 65155968. Its totient is φ = 65123080.

The previous prime is 65139493. The next prime is 65139533. The reversal of 65139523 is 32593156.

It is a happy number.

It is a semiprime because it is the product of two primes, and also a brilliant number, because the two primes have the same length.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-65139523 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (65139533) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 1758 + ... + 11548.

It is an arithmetic number, because the mean of its divisors is an integer number (16288992).

Almost surely, 2^65139523 is an apocalyptic number.

65139523 is a deficient number, since it is larger than the sum of its proper divisors (16445).

65139523 is an equidigital number, since it uses as much as digits as its factorization.

65139523 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 16444.

The product of its digits is 24300, while the sum is 34.

The square root of 65139523 is about 8070.9059590606. The cubic root of 65139523 is about 402.3600542244.

The spelling of 65139523 in words is "sixty-five million, one hundred thirty-nine thousand, five hundred twenty-three".