1221404203 has 4 divisors (see below), whose sum is σ = 1221658920. Its totient is φ = 1221149488.

The previous prime is 1221404201. The next prime is 1221404209. The reversal of 1221404203 is 3024041221.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 3024041221 = 467 ⋅6475463.

It is a cyclic number.

It is not a de Polignac number, because 1221404203 - 2¹ = 1221404201 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (1221404201) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 120025 + ... + 129802.

It is an arithmetic number, because the mean of its divisors is an integer number (305414730).

Almost surely, 2^1221404203 is an apocalyptic number.

1221404203 is a deficient number, since it is larger than the sum of its proper divisors (254717).

1221404203 is an equidigital number, since it uses as much as digits as its factorization.

1221404203 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 254716.

The product of its (nonzero) digits is 384, while the sum is 19.

The square root of 1221404203 is about 34948.5937199195. The cubic root of 1221404203 is about 1068.9395272422.

Adding to 1221404203 its reverse (3024041221), we get a palindrome (4245445424).

The spelling of 1221404203 in words is "one billion, two hundred twenty-one million, four hundred four thousand, two hundred three".