228138461 has 4 divisors (see below), whose sum is σ = 228435900. Its totient is φ = 227841024.

The previous prime is 228138451. The next prime is 228138479. The reversal of 228138461 is 164831822.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 164831822 = 2 ⋅82415911.

It can be written as a sum of positive squares in 2 ways, for example, as 154504900 + 73633561 = 12430^2 + 8581^2 .

It is a cyclic number.

It is not a de Polignac number, because 228138461 - 2²⁶ = 161029597 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 (228138401) 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, 147566 + ... + 149103.

It is an arithmetic number, because the mean of its divisors is an integer number (57108975).

Almost surely, 2^228138461 is an apocalyptic number.

It is an amenable number.

228138461 is a deficient number, since it is larger than the sum of its proper divisors (297439).

228138461 is an equidigital number, since it uses as much as digits as its factorization.

228138461 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 297438.

The product of its digits is 18432, while the sum is 35.

The square root of 228138461 is about 15104.2530765344. The cubic root of 228138461 is about 611.0351152134.

The spelling of 228138461 in words is "two hundred twenty-eight million, one hundred thirty-eight thousand, four hundred sixty-one".