1231313101 has 4 divisors (see below), whose sum is σ = 1231386012. Its totient is φ = 1231240192.

The previous prime is 1231313099. The next prime is 1231313113. The reversal of 1231313101 is 1013131321.

It is a semiprime because it is the product of two primes, and also a brilliant number, because the two primes have the same length.

It can be written as a sum of positive squares in 2 ways, for example, as 1009332900 + 221980201 = 31770^2 + 14899^2 .

It is a cyclic number.

It is not a de Polignac number, because 1231313101 - 2¹ = 1231313099 is a prime.

It is a super-2 number, since 2×1231313101² = 3032263905388472402, which contains 22 as substring.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1231313401) 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, 3405 + ... + 49741.

It is an arithmetic number, because the mean of its divisors is an integer number (307846503).

Almost surely, 2^1231313101 is an apocalyptic number.

It is an amenable number.

1231313101 is a deficient number, since it is larger than the sum of its proper divisors (72911).

1231313101 is an equidigital number, since it uses as much as digits as its factorization.

1231313101 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 72910.

The product of its (nonzero) digits is 54, while the sum is 16.

The square root of 1231313101 is about 35090.0712595458. The cubic root of 1231313101 is about 1071.8224106785.

Adding to 1231313101 its reverse (1013131321), we get a palindrome (2244444422).

The spelling of 1231313101 in words is "one billion, two hundred thirty-one million, three hundred thirteen thousand, one hundred one".