21200099 has 4 divisors (see below), whose sum is σ = 21222120. Its totient is φ = 21178080.

The previous prime is 21200093. The next prime is 21200117. The reversal of 21200099 is 99000212.

It is a semiprime because it is the product of two primes.

It is a cyclic number.

It is not a de Polignac number, because 21200099 - 2⁴ = 21200083 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (21200093) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 9497 + ... + 11514.

It is an arithmetic number, because the mean of its divisors is an integer number (5305530).

Almost surely, 2^21200099 is an apocalyptic number.

21200099 is a deficient number, since it is larger than the sum of its proper divisors (22021).

21200099 is a wasteful number, since it uses less digits than its factorization.

21200099 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 22020.

The product of its (nonzero) digits is 324, while the sum is 23.

The square root of 21200099 is about 4604.3565239890. The cubic root of 21200099 is about 276.7659315424.

The spelling of 21200099 in words is "twenty-one million, two hundred thousand, ninety-nine".