1221121203 has 32 divisors (see below), whose sum is σ = 1822924800. Its totient is φ = 722566656.

The previous prime is 1221121199. The next prime is 1221121259. The reversal of 1221121203 is 3021211221.

It is not a de Polignac number, because 1221121203 - 2² = 1221121199 is a prime.

It is a super-2 number, since 2×1221121203² = 2982273984832334418, which contains 22 as substring.

It is not an unprimeable number, because it can be changed into a prime (1221121003) by changing a digit.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 219150 + ... + 224652.

It is an arithmetic number, because the mean of its divisors is an integer number (56966400).

Almost surely, 2^1221121203 is an apocalyptic number.

1221121203 is a deficient number, since it is larger than the sum of its proper divisors (601803597).

1221121203 is a wasteful number, since it uses less digits than its factorization.

1221121203 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 5771.

The product of its (nonzero) digits is 48, while the sum is 15.

The square root of 1221121203 is about 34944.5446815379. The cubic root of 1221121203 is about 1068.8569629138.

Adding to 1221121203 its reverse (3021211221), we get a palindrome (4242332424).

The spelling of 1221121203 in words is "one billion, two hundred twenty-one million, one hundred twenty-one thousand, two hundred three".