1222400400 has 240 divisors, whose sum is σ = 4257060864. Its totient is φ = 298045440.

The previous prime is 1222400369. The next prime is 1222400429. The reversal of 1222400400 is 40042221.

It is a tau number, because it is divible by the number of its divisors (240).

It is a Harshad number since it is a multiple of its sum of digits (15).

It is a self number, because there is not a number n which added to its sum of digits gives 1222400400.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 47 ways as a sum of consecutive naturals, for example, 1980892 + ... + 1981508.

Almost surely, 2^1222400400 is an apocalyptic number.

1222400400 is a gapful number since it is divisible by the number (10) 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 1222400400, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (2128530432).

1222400400 is an abundant number, since it is smaller than the sum of its proper divisors (3034660464).

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

1222400400 is a wasteful number, since it uses less digits than its factorization.

1222400400 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 778 (or 767 counting only the distinct ones).

The product of its (nonzero) digits is 128, while the sum is 15.

The square root of 1222400400 is about 34962.8431338185. The cubic root of 1222400400 is about 1069.2300630504.

Adding to 1222400400 its reverse (40042221), we get a palindrome (1262442621).

The spelling of 1222400400 in words is "one billion, two hundred twenty-two million, four hundred thousand, four hundred".