231513983281 has 9 divisors (see below), whose sum is σ = 269316102699. Its totient is φ = 198437670144.

The previous prime is 231513983269. The next prime is 231513983333. The reversal of 231513983281 is 182389315132.

The square root of 231513983281 is 481159.

It is a perfect power (a square), and thus also a powerful number.

It can be written as a sum of positive squares in only one way, i.e., 70700151025 + 160813832256 = 265895^2 + 401016^2 .

It is not a de Polignac number, because 231513983281 - 2⁵ = 231513983249 is a prime.

It is a super-2 number, since 2×231513983281² (a number of 24 digits) contains 22 as substring.

It is not an unprimeable number, because it can be changed into a prime (231513983201) by changing a digit.

It is a polite number, since it can be written in 8 ways as a sum of consecutive naturals, for example, 3333745 + ... + 3402481.

It is an arithmetic number, because the mean of its divisors is an integer number (29924011411).

Almost surely, 2^231513983281 is an apocalyptic number.

231513983281 is the 481159-th square number.

231513983281 is the 240580-th centered octagonal number.

It is an amenable number.

231513983281 is a deficient number, since it is larger than the sum of its proper divisors (37802119418).

231513983281 is an frugal number, since it uses more digits than its factorization.

231513983281 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 137488 (or 68744 counting only the distinct ones).

The product of its digits is 311040, while the sum is 46.

The spelling of 231513983281 in words is "two hundred thirty-one billion, five hundred thirteen million, nine hundred eighty-three thousand, two hundred eighty-one".