11778142181 has 12 divisors (see below), whose sum is σ = 13504075812. Its totient is φ = 10232591616.

The previous prime is 11778142177. The next prime is 11778142193. The reversal of 11778142181 is 18124187711.

It can be written as a sum of positive squares in 6 ways, for example, as 2206650625 + 9571491556 = 46975^2 + 97834^2 .

It is not a de Polignac number, because 11778142181 - 2² = 11778142177 is a prime.

It is a super-2 number, since 2×11778142181² (a number of 21 digits) contains 22 as substring.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (11778142171) by changing a digit.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 2046926 + ... + 2052671.

It is an arithmetic number, because the mean of its divisors is an integer number (1125339651).

Almost surely, 2^11778142181 is an apocalyptic number.

It is an amenable number.

11778142181 is a deficient number, since it is larger than the sum of its proper divisors (1725933631).

11778142181 is a wasteful number, since it uses less digits than its factorization.

11778142181 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 4099640 (or 4099627 counting only the distinct ones).

The product of its digits is 25088, while the sum is 41.

The spelling of 11778142181 in words is "eleven billion, seven hundred seventy-eight million, one hundred forty-two thousand, one hundred eighty-one".