1243235155 has 4 divisors (see below), whose sum is σ = 1491882192. Its totient is φ = 994588120.

The previous prime is 1243235141. The next prime is 1243235167. The reversal of 1243235155 is 5515323421.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 5515323421 = 2281 ⋅2417941.

It is not a de Polignac number, because 1243235155 - 2²⁵ = 1209680723 is a prime.

It is a Duffinian number.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 124323511 + ... + 124323520.

It is an arithmetic number, because the mean of its divisors is an integer number (372970548).

Almost surely, 2^1243235155 is an apocalyptic number.

1243235155 is a deficient number, since it is larger than the sum of its proper divisors (248647037).

1243235155 is an equidigital number, since it uses as much as digits as its factorization.

1243235155 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 248647036.

The product of its digits is 18000, while the sum is 31.

The square root of 1243235155 is about 35259.5399147521. The cubic root of 1243235155 is about 1075.2705733198.

Adding to 1243235155 its reverse (5515323421), we get a palindrome (6758558576).

The spelling of 1243235155 in words is "one billion, two hundred forty-three million, two hundred thirty-five thousand, one hundred fifty-five".