1231201212133 has 4 divisors (see below), whose sum is σ = 1231245163008. Its totient is φ = 1231157261260.

The previous prime is 1231201212089. The next prime is 1231201212191. The reversal of 1231201212133 is 3312121021321.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4.

It is a cyclic number.

It is not a de Polignac number, because 1231201212133 - 2²⁵ = 1231167657701 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 (1231201218133) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (23) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 21933391 + ... + 21989452.

It is an arithmetic number, because the mean of its divisors is an integer number (307811290752).

Almost surely, 2^{1231201212133} is an apocalyptic number.

It is an amenable number.

1231201212133 is a deficient number, since it is larger than the sum of its proper divisors (43950875).

1231201212133 is an equidigital number, since it uses as much as digits as its factorization.

1231201212133 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 43950874.

The product of its (nonzero) digits is 432, while the sum is 22.

Adding to 1231201212133 its reverse (3312121021321), we get a palindrome (4543322233454).

The spelling of 1231201212133 in words is "one trillion, two hundred thirty-one billion, two hundred one million, two hundred twelve thousand, one hundred thirty-three".