21303197 has 8 divisors (see below), whose sum is σ = 22110840. Its totient is φ = 20500480.

The previous prime is 21303187. The next prime is 21303203. The reversal of 21303197 is 79130312.

It can be written as a sum of positive squares in 4 ways, for example, as 1819801 + 19483396 = 1349^2 + 4414^2 .

It is a sphenic number, since it is the product of 3 distinct primes.

It is a cyclic number.

It is not a de Polignac number, because 21303197 - 2¹² = 21299101 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 (21303127) 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 7 ways as a sum of consecutive naturals, for example, 9197 + ... + 11277.

It is an arithmetic number, because the mean of its divisors is an integer number (2763855).

Almost surely, 2^21303197 is an apocalyptic number.

It is an amenable number.

21303197 is a deficient number, since it is larger than the sum of its proper divisors (807643).

21303197 is a wasteful number, since it uses less digits than its factorization.

21303197 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 2463.

The product of its (nonzero) digits is 1134, while the sum is 26.

The square root of 21303197 is about 4615.5386467887. The cubic root of 21303197 is about 277.2138521563.

The spelling of 21303197 in words is "twenty-one million, three hundred three thousand, one hundred ninety-seven".