111978649 has 2 divisors, whose sum is σ = 111978650. Its totient is φ = 111978648.

The previous prime is 111978617. The next prime is 111978679. The reversal of 111978649 is 946879111.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 107433225 + 4545424 = 10365^2 + 2132^2 .

It is a cyclic number.

It is not a de Polignac number, because 111978649 - 2⁵ = 111978617 is a prime.

It is a junction number, because it is equal to n+sod(n) for n = 111978599 and 111978608.

It is not a weakly prime, because it can be changed into another prime (111978679) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 55989324 + 55989325.

It is an arithmetic number, because the mean of its divisors is an integer number (55989325).

Almost surely, 2^111978649 is an apocalyptic number.

It is an amenable number.

111978649 is a deficient number, since it is larger than the sum of its proper divisors (1).

111978649 is an equidigital number, since it uses as much as digits as its factorization.

111978649 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 108864, while the sum is 46.

The square root of 111978649 is about 10581.9964562459. The cubic root of 111978649 is about 481.9978205626.

The spelling of 111978649 in words is "one hundred eleven million, nine hundred seventy-eight thousand, six hundred forty-nine".