1221573204 has 96 divisors (see below), whose sum is σ = 3284184960. Its totient is φ = 392345856.

The previous prime is 1221573169. The next prime is 1221573211. The reversal of 1221573204 is 4023751221.

1221573204 is digitally balanced in base 4, because in such base it contains all the possibile digits an equal number of times.

It is a Harshad number since it is a multiple of its sum of digits (27).

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 426144 + ... + 429000.

It is an arithmetic number, because the mean of its divisors is an integer number (34210260).

Almost surely, 2^1221573204 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 1221573204, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (1642092480).

1221573204 is an abundant number, since it is smaller than the sum of its proper divisors (2062611756).

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

1221573204 is a wasteful number, since it uses less digits than its factorization.

1221573204 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 3014 (or 3006 counting only the distinct ones).

The product of its (nonzero) digits is 3360, while the sum is 27.

The square root of 1221573204 is about 34951.0114875092. The cubic root of 1221573204 is about 1068.9888266516.

The spelling of 1221573204 in words is "one billion, two hundred twenty-one million, five hundred seventy-three thousand, two hundred four".