228145381 has 2 divisors, whose sum is σ = 228145382. Its totient is φ = 228145380.

The previous prime is 228145339. The next prime is 228145403. The reversal of 228145381 is 183541822.

It is a happy number.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 196953156 + 31192225 = 14034^2 + 5585^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-228145381 is a prime.

It is a super-2 number, since 2×228145381² = 104100629743270322, which contains 22 as substring.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (228145481) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 114072690 + 114072691.

It is an arithmetic number, because the mean of its divisors is an integer number (114072691).

Almost surely, 2^228145381 is an apocalyptic number.

It is an amenable number.

228145381 is a deficient number, since it is larger than the sum of its proper divisors (1).

228145381 is an equidigital number, since it uses as much as digits as its factorization.

228145381 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 15360, while the sum is 34.

The square root of 228145381 is about 15104.4821493489. The cubic root of 228145381 is about 611.0412932163.

The spelling of 228145381 in words is "two hundred twenty-eight million, one hundred forty-five thousand, three hundred eighty-one".