1231123329979 has 4 divisors (see below), whose sum is σ = 1231970628976. Its totient is φ = 1230276030984.

The previous prime is 1231123329959. The next prime is 1231123329983. The reversal of 1231123329979 is 9799233211321.

It is a semiprime because it is the product of two primes.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-1231123329979 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (1231123329929) 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, 423647319 + ... + 423650224.

It is an arithmetic number, because the mean of its divisors is an integer number (307992657244).

Almost surely, 2^{1231123329979} is an apocalyptic number.

1231123329979 is a deficient number, since it is larger than the sum of its proper divisors (847298997).

1231123329979 is an equidigital number, since it uses as much as digits as its factorization.

1231123329979 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 847298996.

The product of its digits is 1102248, while the sum is 52.

The spelling of 1231123329979 in words is "one trillion, two hundred thirty-one billion, one hundred twenty-three million, three hundred twenty-nine thousand, nine hundred seventy-nine".