1221231103 has 4 divisors (see below), whose sum is σ = 1221842808. Its totient is φ = 1220619400.

The previous prime is 1221231101. The next prime is 1221231107. The reversal of 1221231103 is 3011321221.

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 1221231103 - 2¹ = 1221231101 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1221231101) 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, 302848 + ... + 306853.

It is an arithmetic number, because the mean of its divisors is an integer number (305460702).

Almost surely, 2^1221231103 is an apocalyptic number.

1221231103 is a deficient number, since it is larger than the sum of its proper divisors (611705).

1221231103 is an equidigital number, since it uses as much as digits as its factorization.

1221231103 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 611704.

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

The square root of 1221231103 is about 34946.1171376735. The cubic root of 1221231103 is about 1068.8890273958.

Adding to 1221231103 its reverse (3011321221), we get a palindrome (4232552324).

It can be divided in two parts, 1221 and 231103, that added together give a square (232324 = 482²).

The spelling of 1221231103 in words is "one billion, two hundred twenty-one million, two hundred thirty-one thousand, one hundred three".