228375781 has 8 divisors (see below), whose sum is σ = 238362264. Its totient is φ = 218599680.

The previous prime is 228375769. The next prime is 228375827. The reversal of 228375781 is 187573822.

It can be written as a sum of positive squares in 4 ways, for example, as 69388900 + 158986881 = 8330^2 + 12609^2 .

It is a sphenic number, since it is the product of 3 distinct primes.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-228375781 is a prime.

It is a super-2 number, since 2×228375781² = 104310994694719922, which contains 22 as substring.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (228375751) 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 7 ways as a sum of consecutive naturals, for example, 50376 + ... + 54721.

It is an arithmetic number, because the mean of its divisors is an integer number (29795283).

Almost surely, 2^228375781 is an apocalyptic number.

It is an amenable number.

228375781 is a deficient number, since it is larger than the sum of its proper divisors (9986483).

228375781 is a wasteful number, since it uses less digits than its factorization.

228375781 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 105191.

The product of its digits is 188160, while the sum is 43.

The square root of 228375781 is about 15112.1070999381. The cubic root of 228375781 is about 611.2469172913.

The spelling of 228375781 in words is "two hundred twenty-eight million, three hundred seventy-five thousand, seven hundred eighty-one".