1221642304 has 63 divisors (see below), whose sum is σ = 2585243623. Its totient is φ = 572653568.

The previous prime is 1221642293. The next prime is 1221642307. The reversal of 1221642304 is 4032461221.

It is a happy number.

The square root of 1221642304 is 34952.

It is a perfect power (a square), and thus also a powerful number.

It can be written as a sum of positive squares in 4 ways, for example, as 815216704 + 406425600 = 28552^2 + 20160^2 .

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (1221642307) by changing a digit.

It is a polite number, since it can be written in 8 ways as a sum of consecutive naturals, for example, 4753344 + ... + 4753600.

Almost surely, 2^1221642304 is an apocalyptic number.

1221642304 is the 34952-nd square number.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 1221642304

1221642304 is an abundant number, since it is smaller than the sum of its proper divisors (1363601319).

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

1221642304 is an frugal number, since it uses more digits than its factorization.

1221642304 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 560 (or 276 counting only the distinct ones).

The product of its (nonzero) digits is 2304, while the sum is 25.

The cubic root of 1221642304 is about 1069.0089825552.

Multiplying 1221642304 by its sum of digits (25), we get a square (30541057600 = 174760²).

Multiplying 1221642304 by its product of nonzero digits (2304), we get a square (2814663868416 = 1677696²).

The spelling of 1221642304 in words is "one billion, two hundred twenty-one million, six hundred forty-two thousand, three hundred four".