1221103231 has 4 divisors (see below), whose sum is σ = 1233193464. Its totient is φ = 1209013000.

The previous prime is 1221103223. The next prime is 1221103241. The reversal of 1221103231 is 1323011221.

It is a semiprime because it is the product of two primes.

It is a cyclic number.

It is not a de Polignac number, because 1221103231 - 2³ = 1221103223 is a prime.

It is a super-2 number, since 2×1221103231² = 2982186201517278722, which contains 22 as substring.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1221103201) 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, 6044965 + ... + 6045166.

It is an arithmetic number, because the mean of its divisors is an integer number (308298366).

Almost surely, 2^1221103231 is an apocalyptic number.

1221103231 is a deficient number, since it is larger than the sum of its proper divisors (12090233).

1221103231 is a wasteful number, since it uses less digits than its factorization.

1221103231 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 12090232.

The product of its (nonzero) digits is 72, while the sum is 16.

The square root of 1221103231 is about 34944.2875302960. The cubic root of 1221103231 is about 1068.8517192106.

Adding to 1221103231 its reverse (1323011221), we get a palindrome (2544114452).

The spelling of 1221103231 in words is "one billion, two hundred twenty-one million, one hundred three thousand, two hundred thirty-one".