22211991 has 12 divisors (see below), whose sum is σ = 32610760. Its totient is φ = 14564880.

The previous prime is 22211983. The next prime is 22211993. The reversal of 22211991 is 19911222.

It is not a de Polignac number, because 22211991 - 2³ = 22211983 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (22211993) by changing a digit.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 19681 + ... + 20778.

Almost surely, 2^22211991 is an apocalyptic number.

22211991 is a deficient number, since it is larger than the sum of its proper divisors (10398769).

22211991 is a wasteful number, since it uses less digits than its factorization.

22211991 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 40526 (or 40523 counting only the distinct ones).

The product of its digits is 648, while the sum is 27.

The square root of 22211991 is about 4712.9598979834. The cubic root of 22211991 is about 281.1010684088.

The spelling of 22211991 in words is "twenty-two million, two hundred eleven thousand, nine hundred ninety-one".