228137791 has 4 divisors (see below), whose sum is σ = 260728912. Its totient is φ = 195546672.

The previous prime is 228137783. The next prime is 228137821. The reversal of 228137791 is 197731822.

It is a happy number.

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

It is a cyclic number.

It is not a de Polignac number, because 228137791 - 2³ = 228137783 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 (228137761) 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, 16295550 + ... + 16295563.

It is an arithmetic number, because the mean of its divisors is an integer number (65182228).

Almost surely, 2^228137791 is an apocalyptic number.

228137791 is a deficient number, since it is larger than the sum of its proper divisors (32591121).

228137791 is an equidigital number, since it uses as much as digits as its factorization.

228137791 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 32591120.

The product of its digits is 42336, while the sum is 40.

The square root of 228137791 is about 15104.2308973347. The cubic root of 228137791 is about 611.0345170475.

The spelling of 228137791 in words is "two hundred twenty-eight million, one hundred thirty-seven thousand, seven hundred ninety-one".