1221304664 has 16 divisors (see below), whose sum is σ = 2290369200. Its totient is φ = 610539552.

The previous prime is 1221304663. The next prime is 1221304691. The reversal of 1221304664 is 4664031221.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1221304663) by changing a digit.

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 3 ways as a sum of consecutive naturals, for example, 48029 + ... + 68915.

It is an arithmetic number, because the mean of its divisors is an integer number (143148075).

Almost surely, 2^1221304664 is an apocalyptic number.

It is an amenable number.

1221304664 is a deficient number, since it is larger than the sum of its proper divisors (1069064536).

1221304664 is a wasteful number, since it uses less digits than its factorization.

1221304664 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 28202 (or 28198 counting only the distinct ones).

The product of its (nonzero) digits is 6912, while the sum is 29.

The square root of 1221304664 is about 34947.1696135753. The cubic root of 1221304664 is about 1068.9104885172.

Adding to 1221304664 its reverse (4664031221), we get a palindrome (5885335885).

The spelling of 1221304664 in words is "one billion, two hundred twenty-one million, three hundred four thousand, six hundred sixty-four".