21211230 has 32 divisors (see below), whose sum is σ = 51365664. Its totient is φ = 5605376.

The previous prime is 21211217. The next prime is 21211237. The reversal of 21211230 is 3211212.

It is a super-2 number, since 2×21211230² = 899832556225800, which contains 22 as substring.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21211237) 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, 262 + ... + 6518.

It is an arithmetic number, because the mean of its divisors is an integer number (1605177).

Almost surely, 2^21211230 is an apocalyptic number.

21211230 is an abundant number, since it is smaller than the sum of its proper divisors (30154434).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

21211230 is a wasteful number, since it uses less digits than its factorization.

21211230 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 6380.

The product of its (nonzero) digits is 24, while the sum is 12.

The square root of 21211230 is about 4605.5651119054. The cubic root of 21211230 is about 276.8143612310.

Adding to 21211230 its reverse (3211212), we get a palindrome (24422442).

The spelling of 21211230 in words is "twenty-one million, two hundred eleven thousand, two hundred thirty".