11157831731818 has 4 divisors (see below), whose sum is σ = 16736747597730. Its totient is φ = 5578915865908.

The previous prime is 11157831731791. The next prime is 11157831731819. The reversal of 11157831731818 is 81813713875111.

It is a semiprime because it is the product of two primes.

It can be written as a sum of positive squares in only one way, i.e., 10920533172129 + 237298559689 = 3304623^2 + 487133^2 .

It is not an unprimeable number, because it can be changed into a prime (11157831731819) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 2789457932953 + ... + 2789457932956.

Almost surely, 2^{11157831731818} is an apocalyptic number.

11157831731818 is a deficient number, since it is larger than the sum of its proper divisors (5578915865912).

11157831731818 is an equidigital number, since it uses as much as digits as its factorization.

11157831731818 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 5578915865911.

The product of its digits is 1128960, while the sum is 55.

The spelling of 11157831731818 in words is "eleven trillion, one hundred fifty-seven billion, eight hundred thirty-one million, seven hundred thirty-one thousand, eight hundred eighteen".