228187813 has 4 divisors (see below), whose sum is σ = 260786080. Its totient is φ = 195589548.

The previous prime is 228187801. The next prime is 228187829. The reversal of 228187813 is 318781822.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4, and also an emirpimes, since its reverse is a distinct semiprime: 318781822 = 2 ⋅159390911.

It is a de Polignac number, because none of the positive numbers 2^k-228187813 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 (228187873) 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, 16299123 + ... + 16299136.

It is an arithmetic number, because the mean of its divisors is an integer number (65196520).

Almost surely, 2^228187813 is an apocalyptic number.

It is an amenable number.

228187813 is a deficient number, since it is larger than the sum of its proper divisors (32598267).

228187813 is an equidigital number, since it uses as much as digits as its factorization.

228187813 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 32598266.

The product of its digits is 43008, while the sum is 40.

The square root of 228187813 is about 15105.8867002239. The cubic root of 228187813 is about 611.0791727135.

The spelling of 228187813 in words is "two hundred twenty-eight million, one hundred eighty-seven thousand, eight hundred thirteen".