21818210232 has 128 divisors (see below), whose sum is σ = 68399976960. Its totient is φ = 5645652480.

The previous prime is 21818210231. The next prime is 21818210263. The reversal of 21818210232 is 23201281812.

It is a self number, because there is not a number n which added to its sum of digits gives 21818210232.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21818210231) by changing a digit.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 21507 + ... + 209997.

It is an arithmetic number, because the mean of its divisors is an integer number (534374820).

Almost surely, 2^21818210232 is an apocalyptic number.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 21818210232, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (34199988480).

21818210232 is an abundant number, since it is smaller than the sum of its proper divisors (46581766728).

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

21818210232 is a wasteful number, since it uses less digits than its factorization.

21818210232 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 188573 (or 188569 counting only the distinct ones).

The product of its (nonzero) digits is 3072, while the sum is 30.

The spelling of 21818210232 in words is "twenty-one billion, eight hundred eighteen million, two hundred ten thousand, two hundred thirty-two".