1221322200 has 96 divisors (see below), whose sum is σ = 4326984960. Its totient is φ = 279158400.

The previous prime is 1221322127. The next prime is 1221322231. The reversal of 1221322200 is 22231221.

It is a happy number.

1221322200 is digitally balanced in base 4, because in such base it contains all the possibile digits an equal number of times.

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 1221322200.

It is a congruent number.

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, 141196 + ... + 149595.

It is an arithmetic number, because the mean of its divisors is an integer number (45072760).

Almost surely, 2^1221322200 is an apocalyptic number.

1221322200 is a gapful number since it is divisible by the number (10) formed by its first and last digit.

It is an amenable number.

1221322200 is an abundant number, since it is smaller than the sum of its proper divisors (3105662760).

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

1221322200 is a wasteful number, since it uses less digits than its factorization.

1221322200 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 290817 (or 290808 counting only the distinct ones).

The product of its (nonzero) digits is 96, while the sum is 15.

The square root of 1221322200 is about 34947.4205056682. The cubic root of 1221322200 is about 1068.9156044464.

Adding to 1221322200 its reverse (22231221), we get a palindrome (1243553421).

The spelling of 1221322200 in words is "one billion, two hundred twenty-one million, three hundred twenty-two thousand, two hundred".