111111122121157 has 2 divisors, whose sum is σ = 111111122121158. Its totient is φ = 111111122121156.

The previous prime is 111111122121143. The next prime is 111111122121187. The reversal of 111111122121157 is 751121221111111.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 106370221196836 + 4740900924321 = 10313594^2 + 2177361^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-111111122121157 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (111111122121187) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 55555561060578 + 55555561060579.

It is an arithmetic number, because the mean of its divisors is an integer number (55555561060579).

Almost surely, 2^{111111122121157} is an apocalyptic number.

It is an amenable number.

111111122121157 is a deficient number, since it is larger than the sum of its proper divisors (1).

111111122121157 is an equidigital number, since it uses as much as digits as its factorization.

111111122121157 is an evil number, because the sum of its binary digits is even.

The product of its digits is 280, while the sum is 28.

Adding to 111111122121157 its reverse (751121221111111), we get a palindrome (862232343232268).

The spelling of 111111122121157 in words is "one hundred eleven trillion, one hundred eleven billion, one hundred twenty-two million, one hundred twenty-one thousand, one hundred fifty-seven".