228576991 has 2 divisors, whose sum is σ = 228576992. Its totient is φ = 228576990.

The previous prime is 228576989. The next prime is 228577001. The reversal of 228576991 is 199675822.

It is a weak prime.

It is a cyclic number.

It is not a de Polignac number, because 228576991 - 2¹ = 228576989 is a prime.

It is a super-2 number, since 2×228576991² = 104494881629228162, which contains 22 as substring.

Together with 228576989, 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 (228576191) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 114288495 + 114288496.

It is an arithmetic number, because the mean of its divisors is an integer number (114288496).

Almost surely, 2^228576991 is an apocalyptic number.

228576991 is a deficient number, since it is larger than the sum of its proper divisors (1).

228576991 is an equidigital number, since it uses as much as digits as its factorization.

228576991 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 544320, while the sum is 49.

The square root of 228576991 is about 15118.7628792835. The cubic root of 228576991 is about 611.4263771996.

The spelling of 228576991 in words is "two hundred twenty-eight million, five hundred seventy-six thousand, nine hundred ninety-one".