111921917 has 2 divisors, whose sum is σ = 111921918. Its totient is φ = 111921916.

The previous prime is 111921911. The next prime is 111921947. The reversal of 111921917 is 719129111.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 89321401 + 22600516 = 9451^2 + 4754^2 .

It is a cyclic number.

It is not a de Polignac number, because 111921917 - 2⁸ = 111921661 is a prime.

It is a Chen prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (111921911) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 55960958 + 55960959.

It is an arithmetic number, because the mean of its divisors is an integer number (55960959).

Almost surely, 2^111921917 is an apocalyptic number.

It is an amenable number.

111921917 is a deficient number, since it is larger than the sum of its proper divisors (1).

111921917 is an equidigital number, since it uses as much as digits as its factorization.

111921917 is an evil number, because the sum of its binary digits is even.

The product of its digits is 1134, while the sum is 32.

The square root of 111921917 is about 10579.3155260631. The cubic root of 111921917 is about 481.9164082582.

The spelling of 111921917 in words is "one hundred eleven million, nine hundred twenty-one thousand, nine hundred seventeen".