21222054 has 64 divisors (see below), whose sum is σ = 56263680. Its totient is φ = 5797440.

The previous prime is 21222043. The next prime is 21222143. The reversal of 21222054 is 45022212.

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

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 7474 + ... + 9914.

It is an arithmetic number, because the mean of its divisors is an integer number (879120).

Almost surely, 2^21222054 is an apocalyptic number.

It is a practical number, because each smaller number is the sum of distinct divisors of 21222054, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (28131840).

21222054 is an abundant number, since it is smaller than the sum of its proper divisors (35041626).

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

21222054 is a wasteful number, since it uses less digits than its factorization.

21222054 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2482 (or 2476 counting only the distinct ones).

The product of its (nonzero) digits is 320, while the sum is 18.

The square root of 21222054 is about 4606.7400621264. The cubic root of 21222054 is about 276.8614389525.

Adding to 21222054 its reverse (45022212), we get a palindrome (66244266).

The spelling of 21222054 in words is "twenty-one million, two hundred twenty-two thousand, fifty-four".