21300999 has 16 divisors (see below), whose sum is σ = 29475840. Its totient is φ = 13668480.

The previous prime is 21300997. The next prime is 21301031. The reversal of 21300999 is 99900312.

It is not a de Polignac number, because 21300999 - 2¹ = 21300997 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21300997) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 20607 + ... + 21615.

It is an arithmetic number, because the mean of its divisors is an integer number (1842240).

Almost surely, 2^21300999 is an apocalyptic number.

21300999 is a deficient number, since it is larger than the sum of its proper divisors (8174841).

21300999 is a wasteful number, since it uses less digits than its factorization.

21300999 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1270.

The product of its (nonzero) digits is 4374, while the sum is 33.

The square root of 21300999 is about 4615.3005319264. The cubic root of 21300999 is about 277.2043177970.

The spelling of 21300999 in words is "twenty-one million, three hundred thousand, nine hundred ninety-nine".