21922691 has 8 divisors (see below), whose sum is σ = 25083744. Its totient is φ = 18768960.

The previous prime is 21922687. The next prime is 21922697. The reversal of 21922691 is 19622912.

It is a sphenic number, since it is the product of 3 distinct primes.

It is not a de Polignac number, because 21922691 - 2² = 21922687 is a prime.

It is not an unprimeable number, because it can be changed into a prime (21922697) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 8471 + ... + 10751.

It is an arithmetic number, because the mean of its divisors is an integer number (3135468).

Almost surely, 2^21922691 is an apocalyptic number.

21922691 is a deficient number, since it is larger than the sum of its proper divisors (3161053).

21922691 is a wasteful number, since it uses less digits than its factorization.

21922691 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 3661.

The product of its digits is 3888, while the sum is 32.

The square root of 21922691 is about 4682.1673400253. The cubic root of 21922691 is about 279.8753314049.

The spelling of 21922691 in words is "twenty-one million, nine hundred twenty-two thousand, six hundred ninety-one".