1221401152 has 42 divisors (see below), whose sum is σ = 2484493634. Its totient is φ = 595752960.

The previous prime is 1221401053. The next prime is 1221401161. The reversal of 1221401152 is 2511041221.

It can be written as a sum of positive squares in 3 ways, for example, as 98883136 + 1122518016 = 9944^2 + 33504^2 .

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 5 ways as a sum of consecutive naturals, for example, 101908 + ... + 113260.

Almost surely, 2^1221401152 is an apocalyptic number.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 1221401152, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (1242246817).

1221401152 is an abundant number, since it is smaller than the sum of its proper divisors (1263092482).

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

1221401152 is an equidigital number, since it uses as much as digits as its factorization.

1221401152 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 11447 (or 11396 counting only the distinct ones).

The product of its (nonzero) digits is 160, while the sum is 19.

The square root of 1221401152 is about 34948.5500700673. The cubic root of 1221401152 is about 1068.9386371909.

Adding to 1221401152 its reverse (2511041221), we get a palindrome (3732442373).

The spelling of 1221401152 in words is "one billion, two hundred twenty-one million, four hundred one thousand, one hundred fifty-two".