21442122 has 48 divisors (see below), whose sum is σ = 51219168. Its totient is φ = 6441120.

The previous prime is 21442103. The next prime is 21442133. The reversal of 21442122 is 22124412.

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

It is a junction number, because it is equal to n+sod(n) for n = 21442095 and 21442104.

It is an unprimeable number.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 8997 + ... + 11127.

It is an arithmetic number, because the mean of its divisors is an integer number (1067066).

Almost surely, 2^21442122 is an apocalyptic number.

It is a practical number, because each smaller number is the sum of distinct divisors of 21442122, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (25609584).

21442122 is an abundant number, since it is smaller than the sum of its proper divisors (29777046).

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

21442122 is a wasteful number, since it uses less digits than its factorization.

21442122 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2195 (or 2192 counting only the distinct ones).

The product of its digits is 256, while the sum is 18.

The square root of 21442122 is about 4630.5638965465. The cubic root of 21442122 is about 277.8151471977.

Adding to 21442122 its reverse (22124412), we get a palindrome (43566534).

The spelling of 21442122 in words is "twenty-one million, four hundred forty-two thousand, one hundred twenty-two".