65149236509 has 4 divisors (see below), whose sum is σ = 74456270304. Its totient is φ = 55842202716.

The previous prime is 65149236491. The next prime is 65149236517. The reversal of 65149236509 is 90563294156.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-65149236509 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (65149206509) 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, 4653516887 + ... + 4653516900.

It is an arithmetic number, because the mean of its divisors is an integer number (18614067576).

Almost surely, 2^65149236509 is an apocalyptic number.

It is an amenable number.

65149236509 is a deficient number, since it is larger than the sum of its proper divisors (9307033795).

65149236509 is an equidigital number, since it uses as much as digits as its factorization.

65149236509 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 9307033794.

The product of its (nonzero) digits is 1749600, while the sum is 50.

The spelling of 65149236509 in words is "sixty-five billion, one hundred forty-nine million, two hundred thirty-six thousand, five hundred nine".