231661345 has 8 divisors (see below), whose sum is σ = 278188776. Its totient is φ = 185198976.

The previous prime is 231661333. The next prime is 231661349. The reversal of 231661345 is 543166132.

It can be written as a sum of positive squares in 4 ways, for example, as 78074896 + 153586449 = 8836^2 + 12393^2 .

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

It is a cyclic number.

It is not a de Polignac number, because 231661345 - 2⁹ = 231660833 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (231661349) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 8052 + ... + 22981.

It is an arithmetic number, because the mean of its divisors is an integer number (34773597).

Almost surely, 2^231661345 is an apocalyptic number.

It is an amenable number.

231661345 is a deficient number, since it is larger than the sum of its proper divisors (46527431).

231661345 is a wasteful number, since it uses less digits than its factorization.

231661345 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 32531.

The product of its digits is 12960, while the sum is 31.

The square root of 231661345 is about 15220.4252568711. The cubic root of 231661345 is about 614.1642380902.

The spelling of 231661345 in words is "two hundred thirty-one million, six hundred sixty-one thousand, three hundred forty-five".