228687581 has 2 divisors, whose sum is σ = 228687582. Its totient is φ = 228687580.

The previous prime is 228687577. The next prime is 228687583. The reversal of 228687581 is 185786822.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 209062681 + 19624900 = 14459^2 + 4430^2 .

It is a cyclic number.

It is not a de Polignac number, because 228687581 - 2² = 228687577 is a prime.

It is a super-2 number, since 2×228687581² = 104596019407263122, which contains 22 as substring.

Together with 228687583, it forms a pair of twin primes.

It is a Chen prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (228687583) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 114343790 + 114343791.

It is an arithmetic number, because the mean of its divisors is an integer number (114343791).

Almost surely, 2^228687581 is an apocalyptic number.

It is an amenable number.

228687581 is a deficient number, since it is larger than the sum of its proper divisors (1).

228687581 is an equidigital number, since it uses as much as digits as its factorization.

228687581 is an evil number, because the sum of its binary digits is even.

The product of its digits is 430080, while the sum is 47.

The square root of 228687581 is about 15122.4198129797. The cubic root of 228687581 is about 611.5249679644.

The spelling of 228687581 in words is "two hundred twenty-eight million, six hundred eighty-seven thousand, five hundred eighty-one".