111219721 has 2 divisors, whose sum is σ = 111219722. Its totient is φ = 111219720.

The previous prime is 111219679. The next prime is 111219781. The reversal of 111219721 is 127912111.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 64979721 + 46240000 = 8061^2 + 6800^2 .

It is a cyclic number.

It is not a de Polignac number, because 111219721 - 2⁹ = 111219209 is a prime.

It is not a weakly prime, because it can be changed into another prime (111219781) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 55609860 + 55609861.

It is an arithmetic number, because the mean of its divisors is an integer number (55609861).

Almost surely, 2^111219721 is an apocalyptic number.

It is an amenable number.

111219721 is a deficient number, since it is larger than the sum of its proper divisors (1).

111219721 is an equidigital number, since it uses as much as digits as its factorization.

111219721 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 252, while the sum is 25.

The square root of 111219721 is about 10546.0760949274. The cubic root of 111219721 is about 480.9064483236.

The spelling of 111219721 in words is "one hundred eleven million, two hundred nineteen thousand, seven hundred twenty-one".