11765378781 has 24 divisors (see below), whose sum is σ = 18357052896. Its totient is φ = 7218335520.

The previous prime is 11765378773. The next prime is 11765378783. The reversal of 11765378781 is 18787356711.

It is not a de Polignac number, because 11765378781 - 2³ = 11765378773 is a prime.

It is a super-2 number, since 2×11765378781² (a number of 21 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 (11765378783) by changing a digit.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 113175 + ... + 190628.

It is an arithmetic number, because the mean of its divisors is an integer number (764877204).

Almost surely, 2^11765378781 is an apocalyptic number.

It is an amenable number.

11765378781 is a deficient number, since it is larger than the sum of its proper divisors (6591674115).

11765378781 is a wasteful number, since it uses less digits than its factorization.

11765378781 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 304153 (or 304150 counting only the distinct ones).

The product of its digits is 1975680, while the sum is 54.

The spelling of 11765378781 in words is "eleven billion, seven hundred sixty-five million, three hundred seventy-eight thousand, seven hundred eighty-one".