231228187 has 4 divisors (see below), whose sum is σ = 232701136. Its totient is φ = 229755240.

The previous prime is 231228161. The next prime is 231228199. The reversal of 231228187 is 781822132.

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-231228187 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (231226187) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 736239 + ... + 736552.

It is an arithmetic number, because the mean of its divisors is an integer number (58175284).

Almost surely, 2^231228187 is an apocalyptic number.

231228187 is a deficient number, since it is larger than the sum of its proper divisors (1472949).

231228187 is a wasteful number, since it uses less digits than its factorization.

231228187 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1472948.

The product of its digits is 10752, while the sum is 34.

The square root of 231228187 is about 15206.1891018098. The cubic root of 231228187 is about 613.7812132740.

The spelling of 231228187 in words is "two hundred thirty-one million, two hundred twenty-eight thousand, one hundred eighty-seven".