1221996288 has 36 divisors (see below), whose sum is σ = 3252294248. Its totient is φ = 407331840.

The previous prime is 1221996283. The next prime is 1221996311. The reversal of 1221996288 is 8826991221.

It is a Harshad number since it is a multiple of its sum of digits (48).

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1221996283) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 794803 + ... + 796338.

Almost surely, 2^1221996288 is an apocalyptic number.

It is an amenable number.

1221996288 is an abundant number, since it is smaller than the sum of its proper divisors (2030297960).

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

1221996288 is an equidigital number, since it uses as much as digits as its factorization.

1221996288 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1591160 (or 1591146 counting only the distinct ones).

The product of its digits is 248832, while the sum is 48.

The square root of 1221996288 is about 34957.0634922329. The cubic root of 1221996288 is about 1069.1122248683.

The spelling of 1221996288 in words is "one billion, two hundred twenty-one million, nine hundred ninety-six thousand, two hundred eighty-eight".