222918991 has 2 divisors, whose sum is σ = 222918992. Its totient is φ = 222918990.

The previous prime is 222918953. The next prime is 222919031. The reversal of 222918991 is 199819222.

It is a weak prime.

It is a cyclic number.

It is not a de Polignac number, because 222918991 - 2⁷ = 222918863 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (222918931) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 111459495 + 111459496.

It is an arithmetic number, because the mean of its divisors is an integer number (111459496).

Almost surely, 2^222918991 is an apocalyptic number.

222918991 is a deficient number, since it is larger than the sum of its proper divisors (1).

222918991 is an equidigital number, since it uses as much as digits as its factorization.

222918991 is an evil number, because the sum of its binary digits is even.

The product of its digits is 46656, while the sum is 43.

The square root of 222918991 is about 14930.4718947527. The cubic root of 222918991 is about 606.3392602338.

The spelling of 222918991 in words is "two hundred twenty-two million, nine hundred eighteen thousand, nine hundred ninety-one".