23221220 has 48 divisors (see below), whose sum is σ = 54129600. Its totient is φ = 8296320.

The previous prime is 23221193. The next prime is 23221223. The reversal of 23221220 is 2212232.

It is a junction number, because it is equal to n+sod(n) for n = 23221195 and 23221204.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (23221223) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 12086 + ... + 13874.

It is an arithmetic number, because the mean of its divisors is an integer number (1127700).

Almost surely, 2^23221220 is an apocalyptic number.

23221220 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 23221220, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (27064800).

23221220 is an abundant number, since it is smaller than the sum of its proper divisors (30908380).

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

23221220 is a wasteful number, since it uses less digits than its factorization.

23221220 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1868 (or 1866 counting only the distinct ones).

The product of its (nonzero) digits is 96, while the sum is 14.

The square root of 23221220 is about 4818.8401094039. The cubic root of 23221220 is about 285.2955587798.

Adding to 23221220 its reverse (2212232), we get a palindrome (25433452).

It can be divided in two parts, 232212 and 20, that added together give a palindrome (232232).

The spelling of 23221220 in words is "twenty-three million, two hundred twenty-one thousand, two hundred twenty".