22400400 has 120 divisors (see below), whose sum is σ = 78325344. Its totient is φ = 5427200.

The previous prime is 22400369. The next prime is 22400419. The reversal of 22400400 is 400422.

It is a tau number, because it is divible by the number of its divisors (120).

It is a Harshad number since it is a multiple of its sum of digits (12).

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 polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 12352 + ... + 14048.

Almost surely, 2^22400400 is an apocalyptic number.

22400400 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 22400400, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (39162672).

22400400 is an abundant number, since it is smaller than the sum of its proper divisors (55924944).

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

22400400 is a wasteful number, since it uses less digits than its factorization.

22400400 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1729 (or 1718 counting only the distinct ones).

The product of its (nonzero) digits is 64, while the sum is 12.

The square root of 22400400 is about 4732.9060840038. The cubic root of 22400400 is about 281.8936272009.

Adding to 22400400 its reverse (400422), we get a palindrome (22800822).

The spelling of 22400400 in words is "twenty-two million, four hundred thousand, four hundred".