1221440200 has 48 divisors (see below), whose sum is σ = 2852356500. Its totient is φ = 486424320.

The previous prime is 1221440197. The next prime is 1221440239. The reversal of 1221440200 is 20441221.

It can be written as a sum of positive squares in 6 ways, for example, as 1088868004 + 132572196 = 32998^2 + 11514^2 .

It is an unprimeable number.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 32466 + ... + 59134.

Almost surely, 2^1221440200 is an apocalyptic number.

1221440200 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 1221440200, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (1426178250).

1221440200 is an abundant number, since it is smaller than the sum of its proper divisors (1630916300).

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

1221440200 is a wasteful number, since it uses less digits than its factorization.

1221440200 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 26914 (or 26905 counting only the distinct ones).

The product of its (nonzero) digits is 128, while the sum is 16.

The square root of 1221440200 is about 34949.1087153879. The cubic root of 1221440200 is about 1068.9500283354.

Adding to 1221440200 its reverse (20441221), we get a palindrome (1241881421).

The spelling of 1221440200 in words is "one billion, two hundred twenty-one million, four hundred forty thousand, two hundred".