1243342121 has 18 divisors (see below), whose sum is σ = 1526487930. Its totient is φ = 1009616832.

The previous prime is 1243342063. The next prime is 1243342127. The reversal of 1243342121 is 1212433421.

It can be written as a sum of positive squares in only one way, i.e., 1242210025 + 1132096 = 35245^2 + 1064^2 .

It is not a de Polignac number, because 1243342121 - 2¹⁸ = 1243079977 is a prime.

It is a super-3 number, since 3×1243342121³ (a number of 28 digits) contains 333 as substring.

It is a Curzon number.

It is not an unprimeable number, because it can be changed into a prime (1243342127) by changing a digit.

It is a polite number, since it can be written in 17 ways as a sum of consecutive naturals, for example, 17456 + ... + 52833.

It is an arithmetic number, because the mean of its divisors is an integer number (84804885).

Almost surely, 2^1243342121 is an apocalyptic number.

It is an amenable number.

1243342121 is a deficient number, since it is larger than the sum of its proper divisors (283145809).

1243342121 is an equidigital number, since it uses as much as digits as its factorization.

1243342121 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 70341 (or 70315 counting only the distinct ones).

The product of its digits is 1152, while the sum is 23.

The square root of 1243342121 is about 35261.0567198432. The cubic root of 1243342121 is about 1075.3014106325.

Adding to 1243342121 its reverse (1212433421), we get a palindrome (2455775542).

The spelling of 1243342121 in words is "one billion, two hundred forty-three million, three hundred forty-two thousand, one hundred twenty-one".