21299994 has 12 divisors (see below), whose sum is σ = 46150026. Its totient is φ = 7099992.

The previous prime is 21299987. The next prime is 21300029. The reversal of 21299994 is 49999212.

It can be written as a sum of positive squares in only one way, i.e., 11471769 + 9828225 = 3387^2 + 3135^2 .

It is a Curzon number.

It is an unprimeable number.

It is a polite number, since it can be written in 5 ways as a sum of consecutive naturals, for example, 591649 + ... + 591684.

Almost surely, 2^21299994 is an apocalyptic number.

21299994 is an abundant number, since it is smaller than the sum of its proper divisors (24850032).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

21299994 is a wasteful number, since it uses less digits than its factorization.

21299994 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1183341 (or 1183338 counting only the distinct ones).

The product of its digits is 104976, while the sum is 45.

The square root of 21299994 is about 4615.1916536586. The cubic root of 21299994 is about 277.1999581467.

The spelling of 21299994 in words is "twenty-one million, two hundred ninety-nine thousand, nine hundred ninety-four".