1223204021 has 16 divisors (see below), whose sum is σ = 1434451200. Its totient is φ = 1032792768.

The previous prime is 1223204011. The next prime is 1223204041. The reversal of 1223204021 is 1204023221.

It is a cyclic number.

It is not a de Polignac number, because 1223204021 - 2²² = 1219009717 is a prime.

It is a Curzon number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1223204011) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 78221 + ... + 92546.

It is an arithmetic number, because the mean of its divisors is an integer number (89653200).

Almost surely, 2^1223204021 is an apocalyptic number.

It is an amenable number.

1223204021 is a deficient number, since it is larger than the sum of its proper divisors (211247179).

1223204021 is a wasteful number, since it uses less digits than its factorization.

1223204021 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 170828.

The product of its (nonzero) digits is 192, while the sum is 17.

The square root of 1223204021 is about 34974.3337463346. Note that the first 3 decimals coincide. The cubic root of 1223204021 is about 1069.4643200380.

Adding to 1223204021 its reverse (1204023221), we get a palindrome (2427227242).

The spelling of 1223204021 in words is "one billion, two hundred twenty-three million, two hundred four thousand, twenty-one".