228769991 has 2 divisors, whose sum is σ = 228769992. Its totient is φ = 228769990.

The previous prime is 228769979. The next prime is 228769997. The reversal of 228769991 is 199967822.

It is a strong prime.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-228769991 is a prime.

It is a Chen prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (228769997) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 114384995 + 114384996.

It is an arithmetic number, because the mean of its divisors is an integer number (114384996).

Almost surely, 2^228769991 is an apocalyptic number.

228769991 is a deficient number, since it is larger than the sum of its proper divisors (1).

228769991 is an equidigital number, since it uses as much as digits as its factorization.

228769991 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 979776, while the sum is 53.

The square root of 228769991 is about 15125.1443298899. The cubic root of 228769991 is about 611.5984156495.

The spelling of 228769991 in words is "two hundred twenty-eight million, seven hundred sixty-nine thousand, nine hundred ninety-one".