21992229 has 36 divisors (see below), whose sum is σ = 38342304. Its totient is φ = 12560184.

The previous prime is 21992227. The next prime is 21992231. The reversal of 21992229 is 92229912.

It is an interprime number because it is at equal distance from previous prime (21992227) and next prime (21992231).

It is not a de Polignac number, because 21992229 - 2¹ = 21992227 is a prime.

It is a junction number, because it is equal to n+sod(n) for n = 21992193 and 21992202.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21992227) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 35 ways as a sum of consecutive naturals, for example, 10984 + ... + 12830.

It is an arithmetic number, because the mean of its divisors is an integer number (1065064).

Almost surely, 2^21992229 is an apocalyptic number.

It is an amenable number.

21992229 is a deficient number, since it is larger than the sum of its proper divisors (16350075).

21992229 is an equidigital number, since it uses as much as digits as its factorization.

21992229 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1876 (or 1857 counting only the distinct ones).

The product of its digits is 11664, while the sum is 36.

The square root of 21992229 is about 4689.5872952745. The cubic root of 21992229 is about 280.1709372899.

The spelling of 21992229 in words is "twenty-one million, nine hundred ninety-two thousand, two hundred twenty-nine".