22156811 has 4 divisors (see below), whose sum is σ = 22363992. Its totient is φ = 21949632.

The previous prime is 22156807. The next prime is 22156819. The reversal of 22156811 is 11865122.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 11865122 = 2 ⋅5932561.

It is a cyclic number.

It is not a de Polignac number, because 22156811 - 2² = 22156807 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (22156819) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 103430 + ... + 103643.

It is an arithmetic number, because the mean of its divisors is an integer number (5590998).

Almost surely, 2^22156811 is an apocalyptic number.

22156811 is a deficient number, since it is larger than the sum of its proper divisors (207181).

22156811 is a wasteful number, since it uses less digits than its factorization.

22156811 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 207180.

The product of its digits is 960, while the sum is 26.

The square root of 22156811 is about 4707.1021871211. The cubic root of 22156811 is about 280.8681008612.

The spelling of 22156811 in words is "twenty-two million, one hundred fifty-six thousand, eight hundred eleven".