21299024 has 20 divisors (see below), whose sum is σ = 41408436. Its totient is φ = 10612992.

The previous prime is 21299017. The next prime is 21299029. The reversal of 21299024 is 42099212.

It can be written as a sum of positive squares in 2 ways, for example, as 868624 + 20430400 = 932^2 + 4520^2 .

It is a Smith number, since the sum of its digits (29) coincides with the sum of the digits of its prime factors.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21299029) 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 3 ways as a sum of consecutive naturals, for example, 2882 + ... + 7134.

Almost surely, 2^21299024 is an apocalyptic number.

It is an amenable number.

21299024 is a deficient number, since it is larger than the sum of its proper divisors (20109412).

21299024 is a wasteful number, since it uses less digits than its factorization.

21299024 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 4574 (or 4568 counting only the distinct ones).

The product of its (nonzero) digits is 2592, while the sum is 29.

The square root of 21299024 is about 4615.0865647353. The cubic root of 21299024 is about 277.1957501950.

The spelling of 21299024 in words is "twenty-one million, two hundred ninety-nine thousand, twenty-four".