21303199 has 4 divisors (see below), whose sum is σ = 22424440. Its totient is φ = 20181960.

The previous prime is 21303187. The next prime is 21303203. The reversal of 21303199 is 99130312.

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

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-21303199 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21303109) 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, 560592 + ... + 560629.

It is an arithmetic number, because the mean of its divisors is an integer number (5606110).

Almost surely, 2^21303199 is an apocalyptic number.

21303199 is a deficient number, since it is larger than the sum of its proper divisors (1121241).

21303199 is a wasteful number, since it uses less digits than its factorization.

21303199 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1121240.

The product of its (nonzero) digits is 1458, while the sum is 28.

The square root of 21303199 is about 4615.5388634481. The cubic root of 21303199 is about 277.2138608315.

It can be divided in two parts, 2130 and 3199, that added together give a square (5329 = 73²).

The spelling of 21303199 in words is "twenty-one million, three hundred three thousand, one hundred ninety-nine".