111697921 has 4 divisors (see below), whose sum is σ = 111719344. Its totient is φ = 111676500.

The previous prime is 111697909. The next prime is 111697933. The reversal of 111697921 is 129796111.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4, and also an emirpimes, since its reverse is a distinct semiprime: 129796111 = 37 ⋅3508003.

It is an interprime number because it is at equal distance from previous prime (111697909) and next prime (111697933).

It is a cyclic number.

It is not a de Polignac number, because 111697921 - 2⁵ = 111697889 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (111697951) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 2746 + ... + 15196.

It is an arithmetic number, because the mean of its divisors is an integer number (27929836).

Almost surely, 2^111697921 is an apocalyptic number.

It is an amenable number.

111697921 is a deficient number, since it is larger than the sum of its proper divisors (21423).

111697921 is an equidigital number, since it uses as much as digits as its factorization.

111697921 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 21422.

The product of its digits is 6804, while the sum is 37.

The square root of 111697921 is about 10568.7237167030. The cubic root of 111697921 is about 481.5946975374.

The spelling of 111697921 in words is "one hundred eleven million, six hundred ninety-seven thousand, nine hundred twenty-one".