1221102243 has 8 divisors (see below), whose sum is σ = 1809040400. Its totient is φ = 814068144.

The previous prime is 1221102229. The next prime is 1221102247. The reversal of 1221102243 is 3422011221.

It is a happy number.

It is not a de Polignac number, because 1221102243 - 2¹² = 1221098147 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (1221102247) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 22612978 + ... + 22613031.

It is an arithmetic number, because the mean of its divisors is an integer number (226130050).

Almost surely, 2^1221102243 is an apocalyptic number.

1221102243 is a deficient number, since it is larger than the sum of its proper divisors (587938157).

1221102243 is an equidigital number, since it uses as much as digits as its factorization.

1221102243 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 45226018 (or 45226012 counting only the distinct ones).

The product of its (nonzero) digits is 192, while the sum is 18.

The square root of 1221102243 is about 34944.2733935047. The cubic root of 1221102243 is about 1068.8514309396.

Adding to 1221102243 its reverse (3422011221), we get a palindrome (4643113464).

The spelling of 1221102243 in words is "one billion, two hundred twenty-one million, one hundred two thousand, two hundred forty-three".