21110022 has 48 divisors (see below), whose sum is σ = 48859200. Its totient is φ = 6564096.

The previous prime is 21109987. The next prime is 21110027. The reversal of 21110022 is 22001112.

It is a Harshad number since it is a multiple of its sum of digits (9).

It is a junction number, because it is equal to n+sod(n) for n = 21109986 and 21110013.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21110027) by changing a digit.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 45363 + ... + 45825.

It is an arithmetic number, because the mean of its divisors is an integer number (1017900).

Almost surely, 2^21110022 is an apocalyptic number.

It is a practical number, because each smaller number is the sum of distinct divisors of 21110022, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (24429600).

21110022 is an abundant number, since it is smaller than the sum of its proper divisors (27749178).

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

21110022 is a wasteful number, since it uses less digits than its factorization.

21110022 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 637 (or 634 counting only the distinct ones).

The product of its (nonzero) digits is 8, while the sum is 9.

The square root of 21110022 is about 4594.5643971981. The cubic root of 21110022 is about 276.3733919122.

Adding to 21110022 its reverse (22001112), we get a palindrome (43111134).

The spelling of 21110022 in words is "twenty-one million, one hundred ten thousand, twenty-two".