228138861 has 16 divisors (see below), whose sum is σ = 322403328. Its totient is φ = 143001600.

The previous prime is 228138847. The next prime is 228138887. The reversal of 228138861 is 168831822.

It is not a de Polignac number, because 228138861 - 2¹¹ = 228136813 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (228138811) 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 15 ways as a sum of consecutive naturals, for example, 73501 + ... + 76541.

It is an arithmetic number, because the mean of its divisors is an integer number (20150208).

Almost surely, 2^228138861 is an apocalyptic number.

It is an amenable number.

228138861 is a deficient number, since it is larger than the sum of its proper divisors (94264467).

228138861 is a wasteful number, since it uses less digits than its factorization.

228138861 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 4532.

The product of its digits is 36864, while the sum is 39.

The square root of 228138861 is about 15104.2663178322. The cubic root of 228138861 is about 611.0354723268.

The spelling of 228138861 in words is "two hundred twenty-eight million, one hundred thirty-eight thousand, eight hundred sixty-one".