21012212130 has 128 divisors (see below), whose sum is σ = 62111605248. Its totient is φ = 4430149632.

The previous prime is 21012212099. The next prime is 21012212153. The reversal of 21012212130 is 3121221012.

It is a super-2 number, since 2×21012212130² (a number of 21 digits) contains 22 as substring.

It is a Harshad number since it is a multiple of its sum of digits (15).

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 63 ways as a sum of consecutive naturals, for example, 7405072 + ... + 7407908.

It is an arithmetic number, because the mean of its divisors is an integer number (485246916).

Almost surely, 2^21012212130 is an apocalyptic number.

It is a practical number, because each smaller number is the sum of distinct divisors of 21012212130, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (31055802624).

21012212130 is an abundant number, since it is smaller than the sum of its proper divisors (41099393118).

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

21012212130 is a wasteful number, since it uses less digits than its factorization.

21012212130 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 5580.

The product of its (nonzero) digits is 48, while the sum is 15.

Adding to 21012212130 its reverse (3121221012), we get a palindrome (24133433142).

The spelling of 21012212130 in words is "twenty-one billion, twelve million, two hundred twelve thousand, one hundred thirty".