228136681 has 2 divisors, whose sum is σ = 228136682. Its totient is φ = 228136680.

The previous prime is 228136627. The next prime is 228136691. The reversal of 228136681 is 186631822.

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., 209989081 + 18147600 = 14491^2 + 4260^2 .

It is a cyclic number.

It is not a de Polignac number, because 228136681 - 2²¹ = 226039529 is a prime.

It is a super-2 number, since 2×228136681² = 104092690435391522, which contains 22 as substring.

It is a self number, because there is not a number n which added to its sum of digits gives 228136681.

It is not a weakly prime, because it can be changed into another prime (228136691) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 114068340 + 114068341.

It is an arithmetic number, because the mean of its divisors is an integer number (114068341).

Almost surely, 2^228136681 is an apocalyptic number.

It is an amenable number.

228136681 is a deficient number, since it is larger than the sum of its proper divisors (1).

228136681 is an equidigital number, since it uses as much as digits as its factorization.

228136681 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 27648, while the sum is 37.

The square root of 228136681 is about 15104.1941526187. The cubic root of 228136681 is about 611.0335260537.

The spelling of 228136681 in words is "two hundred twenty-eight million, one hundred thirty-six thousand, six hundred eighty-one".