111978899 has 2 divisors, whose sum is σ = 111978900. Its totient is φ = 111978898.

The previous prime is 111978887. The next prime is 111978901. The reversal of 111978899 is 998879111.

It is a strong prime.

It is an emirp because it is prime and its reverse (998879111) is a distict prime.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-111978899 is a prime.

Together with 111978901, it forms a pair of twin primes.

It is a Chen prime.

It is a self number, because there is not a number n which added to its sum of digits gives 111978899.

It is not a weakly prime, because it can be changed into another prime (111978809) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 55989449 + 55989450.

It is an arithmetic number, because the mean of its divisors is an integer number (55989450).

Almost surely, 2^111978899 is an apocalyptic number.

111978899 is a deficient number, since it is larger than the sum of its proper divisors (1).

111978899 is an equidigital number, since it uses as much as digits as its factorization.

111978899 is an evil number, because the sum of its binary digits is even.

The product of its digits is 326592, while the sum is 53.

The square root of 111978899 is about 10582.0082687550. The cubic root of 111978899 is about 481.9981792600.

The spelling of 111978899 in words is "one hundred eleven million, nine hundred seventy-eight thousand, eight hundred ninety-nine".