21300231 has 16 divisors (see below), whose sum is σ = 29804544. Its totient is φ = 13505184.

The previous prime is 21300203. The next prime is 21300233. The reversal of 21300231 is 13200312.

It is a happy number.

It is not a de Polignac number, because 21300231 - 2⁵ = 21300199 is a prime.

It is a super-2 number, since 2×21300231² = 907399681306722, which contains 22 as substring.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21300233) 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, 12810 + ... + 14376.

It is an arithmetic number, because the mean of its divisors is an integer number (1862784).

Almost surely, 2^21300231 is an apocalyptic number.

21300231 is a deficient number, since it is larger than the sum of its proper divisors (8504313).

21300231 is a wasteful number, since it uses less digits than its factorization.

21300231 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1790.

The product of its (nonzero) digits is 36, while the sum is 12.

The square root of 21300231 is about 4615.2173296607. The cubic root of 21300231 is about 277.2009862557.

Adding to 21300231 its reverse (13200312), we get a palindrome (34500543).

The spelling of 21300231 in words is "twenty-one million, three hundred thousand, two hundred thirty-one".