22421556 has 96 divisors (see below), whose sum is σ = 61967360. Its totient is φ = 6998400.

The previous prime is 22421551. The next prime is 22421561. The reversal of 22421556 is 65512422.

22421556 is a nontrivial binomial coefficient, being equal to C(6697, 2).

It is an interprime number because it is at equal distance from previous prime (22421551) and next prime (22421561).

It is a super-2 number, since 2×22421556² = 1005452346922272, which contains 22 as substring.

It is a Harshad number since it is a multiple of its sum of digits (27).

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (22421551) 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, 123786 + ... + 123966.

Almost surely, 2^22421556 is an apocalyptic number.

22421556 is the 6696-th triangular number.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 22421556, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (30983680).

22421556 is an abundant number, since it is smaller than the sum of its proper divisors (39545804).

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

22421556 is a wasteful number, since it uses less digits than its factorization.

22421556 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 262 (or 254 counting only the distinct ones).

The product of its digits is 4800, while the sum is 27.

The square root of 22421556 is about 4735.1405470165. The cubic root of 22421556 is about 281.9823438470.

Adding to 22421556 its reverse (65512422), we get a palindrome (87933978).

The spelling of 22421556 in words is "twenty-two million, four hundred twenty-one thousand, five hundred fifty-six".