21903222 has 64 divisors (see below), whose sum is σ = 51093504. Its totient is φ = 6193440.

The previous prime is 21903197. The next prime is 21903229. The reversal of 21903222 is 22230912.

It is a super-2 number, since 2×21903222² = 959502267962568, which contains 22 as substring.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21903229) by changing a digit.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 71193 + ... + 71499.

It is an arithmetic number, because the mean of its divisors is an integer number (798336).

Almost surely, 2^21903222 is an apocalyptic number.

21903222 is a gapful number since it is divisible by the number (22) formed by its first and last digit.

It is a practical number, because each smaller number is the sum of distinct divisors of 21903222, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (25546752).

21903222 is an abundant number, since it is smaller than the sum of its proper divisors (29190282).

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

21903222 is a wasteful number, since it uses less digits than its factorization.

21903222 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 393.

The product of its (nonzero) digits is 432, while the sum is 21.

The square root of 21903222 is about 4680.0878196889. The cubic root of 21903222 is about 279.7924567458.

The spelling of 21903222 in words is "twenty-one million, nine hundred three thousand, two hundred twenty-two".