21224992 has 12 divisors (see below), whose sum is σ = 41786766. Its totient is φ = 10612480.

The previous prime is 21224989. The next prime is 21225037. The reversal of 21224992 is 29942212.

It can be written as a sum of positive squares in only one way, i.e., 20757136 + 467856 = 4556^2 + 684^2 .

It is an unprimeable number.

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 as a sum of consecutive naturals, namely, 331609 + ... + 331672.

Almost surely, 2^21224992 is an apocalyptic number.

It is an amenable number.

21224992 is a deficient number, since it is larger than the sum of its proper divisors (20561774).

21224992 is an equidigital number, since it uses as much as digits as its factorization.

21224992 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 663291 (or 663283 counting only the distinct ones).

The product of its digits is 5184, while the sum is 31.

The square root of 21224992 is about 4607.0589316830. The cubic root of 21224992 is about 276.8742146774.

The spelling of 21224992 in words is "twenty-one million, two hundred twenty-four thousand, nine hundred ninety-two".