231305687 has 4 divisors (see below), whose sum is σ = 241362480. Its totient is φ = 221248896.

The previous prime is 231305629. The next prime is 231305693. The reversal of 231305687 is 786503132.

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

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-231305687 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (231305617) 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 3 ways as a sum of consecutive naturals, for example, 5028362 + ... + 5028407.

It is an arithmetic number, because the mean of its divisors is an integer number (60340620).

Almost surely, 2^231305687 is an apocalyptic number.

231305687 is a deficient number, since it is larger than the sum of its proper divisors (10056793).

231305687 is a wasteful number, since it uses less digits than its factorization.

231305687 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 10056792.

The product of its (nonzero) digits is 30240, while the sum is 35.

The square root of 231305687 is about 15208.7371928112. The cubic root of 231305687 is about 613.8497786325.

The spelling of 231305687 in words is "two hundred thirty-one million, three hundred five thousand, six hundred eighty-seven".