111981019 has 2 divisors, whose sum is σ = 111981020. Its totient is φ = 111981018.

The previous prime is 111981017. The next prime is 111981059. The reversal of 111981019 is 910189111.

It is a weak prime.

It is a cyclic number.

It is not a de Polignac number, because 111981019 - 2¹ = 111981017 is a prime.

It is a super-2 number, since 2×111981019² = 25079497232556722, which contains 22 as substring.

Together with 111981017, it forms a pair of twin primes.

It is not a weakly prime, because it can be changed into another prime (111981017) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 55990509 + 55990510.

It is an arithmetic number, because the mean of its divisors is an integer number (55990510).

Almost surely, 2^111981019 is an apocalyptic number.

111981019 is a deficient number, since it is larger than the sum of its proper divisors (1).

111981019 is an equidigital number, since it uses as much as digits as its factorization.

111981019 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 648, while the sum is 31.

The square root of 111981019 is about 10582.1084383028. The cubic root of 111981019 is about 482.0012209929.

The spelling of 111981019 in words is "one hundred eleven million, nine hundred eighty-one thousand, nineteen".