65342640778251 has 16 divisors (see below), whose sum is σ = 89899933783968. Its totient is φ = 42189064832000.

The previous prime is 65342640778223. The next prime is 65342640778297. The reversal of 65342640778251 is 15287704624356.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-65342640778251 is a prime.

It is not an unprimeable number, because it can be changed into a prime (65342640778211) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 1938818850 + ... + 1938852551.

It is an arithmetic number, because the mean of its divisors is an integer number (5618745861498).

Almost surely, 2^{65342640778251} is an apocalyptic number.

65342640778251 is a deficient number, since it is larger than the sum of its proper divisors (24557293005717).

65342640778251 is a wasteful number, since it uses less digits than its factorization.

65342640778251 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 3877671582.

The product of its (nonzero) digits is 67737600, while the sum is 60.

The spelling of 65342640778251 in words is "sixty-five trillion, three hundred forty-two billion, six hundred forty million, seven hundred seventy-eight thousand, two hundred fifty-one".