21231122130 has 192 divisors, whose sum is σ = 57411514368. Its totient is φ = 5440780800.

The previous prime is 21231122071. The next prime is 21231122137. The reversal of 21231122130 is 3122113212.

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

It is not an unprimeable number, because it can be changed into a prime (21231122137) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written in 95 ways as a sum of consecutive naturals, for example, 61184617 + ... + 61184963.

It is an arithmetic number, because the mean of its divisors is an integer number (299018304).

Almost surely, 2^21231122130 is an apocalyptic number.

It is a practical number, because each smaller number is the sum of distinct divisors of 21231122130, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (28705757184).

21231122130 is an abundant number, since it is smaller than the sum of its proper divisors (36180392238).

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

21231122130 is a wasteful number, since it uses less digits than its factorization.

21231122130 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 641 (or 638 counting only the distinct ones).

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

Adding to 21231122130 its reverse (3122113212), we get a palindrome (24353235342).

The spelling of 21231122130 in words is "twenty-one billion, two hundred thirty-one million, one hundred twenty-two thousand, one hundred thirty".