1231333121 has 8 divisors (see below), whose sum is σ = 1257321864. Its totient is φ = 1205591040.

The previous prime is 1231333111. The next prime is 1231333139. The reversal of 1231333121 is 1213331321.

It can be written as a sum of positive squares in 4 ways, for example, as 486643600 + 744689521 = 22060^2 + 27289^2 .

It is a sphenic number, since it is the product of 3 distinct primes.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-1231333121 is a prime.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 1231333093 and 1231333102.

It is not an unprimeable number, because it can be changed into a prime (1231333111) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 51560 + ... + 71561.

It is an arithmetic number, because the mean of its divisors is an integer number (157165233).

Almost surely, 2^1231333121 is an apocalyptic number.

It is an amenable number.

1231333121 is a deficient number, since it is larger than the sum of its proper divisors (25988743).

1231333121 is a wasteful number, since it uses less digits than its factorization.

1231333121 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 123331.

The product of its digits is 324, while the sum is 20.

The square root of 1231333121 is about 35090.3565242646. The cubic root of 1231333121 is about 1071.8282195905.

Adding to 1231333121 its reverse (1213331321), we get a palindrome (2444664442).

The spelling of 1231333121 in words is "one billion, two hundred thirty-one million, three hundred thirty-three thousand, one hundred twenty-one".