21013122 has 96 divisors (see below), whose sum is σ = 51228288. Its totient is φ = 5710848.

The previous prime is 21013117. The next prime is 21013127. The reversal of 21013122 is 22131012.

It is an interprime number because it is at equal distance from previous prime (21013117) and next prime (21013127).

It is a junction number, because it is equal to n+sod(n) for n = 21013098 and 21013107.

It is not an unprimeable number, because it can be changed into a prime (21013127) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (7) of ones.

It is a polite number, since it can be written in 47 ways as a sum of consecutive naturals, for example, 396448 + ... + 396500.

It is an arithmetic number, because the mean of its divisors is an integer number (533628).

Almost surely, 2^21013122 is an apocalyptic number.

It is a practical number, because each smaller number is the sum of distinct divisors of 21013122, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (25614144).

21013122 is an abundant number, since it is smaller than the sum of its proper divisors (30215166).

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

21013122 is a wasteful number, since it uses less digits than its factorization.

21013122 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 124 (or 111 counting only the distinct ones).

The product of its (nonzero) digits is 24, while the sum is 12.

The square root of 21013122 is about 4584.0071989472. The cubic root of 21013122 is about 275.9498701225.

Adding to 21013122 its reverse (22131012), we get a palindrome (43144134).

The spelling of 21013122 in words is "twenty-one million, thirteen thousand, one hundred twenty-two".