222156891 has 16 divisors (see below), whose sum is σ = 359041920. Its totient is φ = 134640360.

The previous prime is 222156863. The next prime is 222156899. The reversal of 222156891 is 198651222.

222156891 is a `hidden beast` number, since 2 + 2 + 2 + 1 + 568 + 91 = 666.

It is not a de Polignac number, because 222156891 - 2⁵ = 222156859 is a prime.

It is not an unprimeable number, because it can be changed into a prime (222156899) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 373705 + ... + 374298.

It is an arithmetic number, because the mean of its divisors is an integer number (22440120).

Almost surely, 2^222156891 is an apocalyptic number.

222156891 is a deficient number, since it is larger than the sum of its proper divisors (136885029).

222156891 is a wasteful number, since it uses less digits than its factorization.

222156891 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 748023 (or 748017 counting only the distinct ones).

The product of its digits is 17280, while the sum is 36.

The square root of 222156891 is about 14904.9284131122. The cubic root of 222156891 is about 605.6475011050.

The spelling of 222156891 in words is "two hundred twenty-two million, one hundred fifty-six thousand, eight hundred ninety-one".