65136561261 has 16 divisors (see below), whose sum is σ = 87089463360. Its totient is φ = 43304119040.

The previous prime is 65136561241. The next prime is 65136561299. The reversal of 65136561261 is 16216563156.

65136561261 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-65136561261 is a prime.

It is a super-2 number, since 2×65136561261² (a number of 22 digits) contains 22 as substring.

It is a Curzon number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (65136561241) 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, 2817931 + ... + 2840951.

It is an arithmetic number, because the mean of its divisors is an integer number (5443091460).

Almost surely, 2^65136561261 is an apocalyptic number.

It is an amenable number.

65136561261 is a deficient number, since it is larger than the sum of its proper divisors (21952902099).

65136561261 is a wasteful number, since it uses less digits than its factorization.

65136561261 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 25596.

The product of its digits is 194400, while the sum is 42.

The spelling of 65136561261 in words is "sixty-five billion, one hundred thirty-six million, five hundred sixty-one thousand, two hundred sixty-one".