1231121323011 has 4 divisors (see below), whose sum is σ = 1641495097352. Its totient is φ = 820747548672.

The previous prime is 1231121323009. The next prime is 1231121323037. The reversal of 1231121323011 is 1103231211321.

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

It is not a de Polignac number, because 1231121323011 - 2¹ = 1231121323009 is a prime.

It is a super-2 number, since 2×1231121323011² (a number of 25 digits) contains 22 as substring.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (1231121323051) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 205186887166 + ... + 205186887171.

It is an arithmetic number, because the mean of its divisors is an integer number (410373774338).

Almost surely, 2^{1231121323011} is an apocalyptic number.

1231121323011 is a deficient number, since it is larger than the sum of its proper divisors (410373774341).

1231121323011 is an equidigital number, since it uses as much as digits as its factorization.

1231121323011 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 410373774340.

The product of its (nonzero) digits is 216, while the sum is 21.

Adding to 1231121323011 its reverse (1103231211321), we get a palindrome (2334352534332).

The spelling of 1231121323011 in words is "one trillion, two hundred thirty-one billion, one hundred twenty-one million, three hundred twenty-three thousand, eleven".