21130230 has 48 divisors (see below), whose sum is σ = 55751472. Its totient is φ = 5121600.

The previous prime is 21130111. The next prime is 21130231. The reversal of 21130230 is 3203112.

It is a happy number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21130231) by changing a digit.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 720 + ... + 6540.

It is an arithmetic number, because the mean of its divisors is an integer number (1161489).

Almost surely, 2^21130230 is an apocalyptic number.

It is a practical number, because each smaller number is the sum of distinct divisors of 21130230, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (27875736).

21130230 is an abundant number, since it is smaller than the sum of its proper divisors (34621242).

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

21130230 is a wasteful number, since it uses less digits than its factorization.

21130230 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 5853 (or 5842 counting only the distinct ones).

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

The square root of 21130230 is about 4596.7629914974. The cubic root of 21130230 is about 276.4615518132.

Adding to 21130230 its reverse (3203112), we get a palindrome (24333342).

The spelling of 21130230 in words is "twenty-one million, one hundred thirty thousand, two hundred thirty".