111161021 has 2 divisors, whose sum is σ = 111161022. Its totient is φ = 111161020.

The previous prime is 111160949. The next prime is 111161023. The reversal of 111161021 is 120161111.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 105801796 + 5359225 = 10286^2 + 2315^2 .

It is a cyclic number.

It is not a de Polignac number, because 111161021 - 2²⁶ = 44052157 is a prime.

It is a Sophie Germain prime.

Together with 111161023, it forms a pair of twin primes.

It is a Chen prime.

It is a Curzon number.

It is a junction number, because it is equal to n+sod(n) for n = 111160987 and 111161005.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (111161023) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 55580510 + 55580511.

It is an arithmetic number, because the mean of its divisors is an integer number (55580511).

Almost surely, 2^111161021 is an apocalyptic number.

It is an amenable number.

111161021 is a deficient number, since it is larger than the sum of its proper divisors (1).

111161021 is an equidigital number, since it uses as much as digits as its factorization.

111161021 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 12, while the sum is 14.

The square root of 111161021 is about 10543.2927019978. The cubic root of 111161021 is about 480.8218285097.

The spelling of 111161021 in words is "one hundred eleven million, one hundred sixty-one thousand, twenty-one".