22012991 has 16 divisors (see below), whose sum is σ = 29557248. Its totient is φ = 15832800.

The previous prime is 22012981. The next prime is 22013021. The reversal of 22012991 is 19921022.

It is a happy number.

It is a cyclic number.

It is not a de Polignac number, because 22012991 - 2⁶ = 22012927 is a prime.

It is a self number, because there is not a number n which added to its sum of digits gives 22012991.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (22012901) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 9995 + ... + 11996.

It is an arithmetic number, because the mean of its divisors is an integer number (1847328).

Almost surely, 2^22012991 is an apocalyptic number.

22012991 is a deficient number, since it is larger than the sum of its proper divisors (7544257).

22012991 is a wasteful number, since it uses less digits than its factorization.

22012991 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 22022.

The product of its (nonzero) digits is 648, while the sum is 26.

The square root of 22012991 is about 4691.8004006991. The cubic root of 22012991 is about 280.2590756872.

The spelling of 22012991 in words is "twenty-two million, twelve thousand, nine hundred ninety-one".