21231211230 has 96 divisors (see below), whose sum is σ = 58902798240. Its totient is φ = 5290168320.

The previous prime is 21231211229. The next prime is 21231211231. The reversal of 21231211230 is 3211213212.

21231211230 is a `hidden beast` number, since 212 + 312 + 112 + 30 = 666.

It is an interprime number because it is at equal distance from previous prime (21231211229) and next prime (21231211231).

It is a super-2 number, since 2×21231211230² (a number of 21 digits) contains 22 as substring.

It is a Harshad number since it is a multiple of its sum of digits (18).

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21231211231) by changing a digit.

It is a polite number, since it can be written in 47 ways as a sum of consecutive naturals, for example, 39790 + ... + 209870.

It is an arithmetic number, because the mean of its divisors is an integer number (613570815).

Almost surely, 2^21231211230 is an apocalyptic number.

It is a practical number, because each smaller number is the sum of distinct divisors of 21231211230, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (29451399120).

21231211230 is an abundant number, since it is smaller than the sum of its proper divisors (37671587010).

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

21231211230 is a wasteful number, since it uses less digits than its factorization.

21231211230 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 170186 (or 170183 counting only the distinct ones).

The product of its (nonzero) digits is 144, while the sum is 18.

Adding to 21231211230 its reverse (3211213212), we get a palindrome (24442424442).

The spelling of 21231211230 in words is "twenty-one billion, two hundred thirty-one million, two hundred eleven thousand, two hundred thirty".