22100400 has 180 divisors, whose sum is σ = 87750832. Its totient is φ = 5045760.

The previous prime is 22100347. The next prime is 22100431. The reversal of 22100400 is 400122.

It is a tau number, because it is divible by the number of its divisors (180).

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

It is a super Niven number, because it is divisible the sum of any subset of its (nonzero) digits.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 35 ways as a sum of consecutive naturals, for example, 24762 + ... + 25638.

Almost surely, 2^22100400 is an apocalyptic number.

22100400 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 22100400, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (43875416).

22100400 is an abundant number, since it is smaller than the sum of its proper divisors (65650432).

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

22100400 is a wasteful number, since it uses less digits than its factorization.

22100400 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 908 (or 894 counting only the distinct ones).

The product of its (nonzero) digits is 16, while the sum is 9.

The square root of 22100400 is about 4701.1062527877. The cubic root of 22100400 is about 280.6295359078.

Adding to 22100400 its reverse (400122), we get a palindrome (22500522).

It can be divided in two parts, 22100 and 400, that added together give a square (22500 = 150²).

The spelling of 22100400 in words is "twenty-two million, one hundred thousand, four hundred".