1221434121 has 12 divisors (see below), whose sum is σ = 1673789712. Its totient is φ = 792278928.

The previous prime is 1221434119. The next prime is 1221434129. The reversal of 1221434121 is 1214341221.

It is not a de Polignac number, because 1221434121 - 2¹ = 1221434119 is a prime.

It is a Curzon number.

It is not an unprimeable number, because it can be changed into a prime (1221434129) by changing a digit.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 144595 + ... + 152808.

It is an arithmetic number, because the mean of its divisors is an integer number (139482476).

Almost surely, 2^1221434121 is an apocalyptic number.

It is an amenable number.

1221434121 is a deficient number, since it is larger than the sum of its proper divisors (452355591).

1221434121 is an equidigital number, since it uses as much as digits as its factorization.

1221434121 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 297480 (or 297443 counting only the distinct ones).

The product of its digits is 384, while the sum is 21.

The square root of 1221434121 is about 34949.0217459659. The cubic root of 1221434121 is about 1068.9482549758.

Adding to 1221434121 its reverse (1214341221), we get a palindrome (2435775342).

It can be divided in two parts, 1 and 221434121, that added together give a palindrome (221434122).

The spelling of 1221434121 in words is "one billion, two hundred twenty-one million, four hundred thirty-four thousand, one hundred twenty-one".