268689991 has 2 divisors, whose sum is σ = 268689992. Its totient is φ = 268689990.

The previous prime is 268689983. The next prime is 268690013. The reversal of 268689991 is 199986862.

It is a weak prime.

It is a cyclic number.

It is not a de Polignac number, because 268689991 - 2³ = 268689983 is a prime.

It is a super-2 number, since 2×268689991² = 144388622527160162, which contains 22 as substring.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (268689961) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 134344995 + 134344996.

It is an arithmetic number, because the mean of its divisors is an integer number (134344996).

Almost surely, 2^268689991 is an apocalyptic number.

268689991 is a deficient number, since it is larger than the sum of its proper divisors (1).

268689991 is an equidigital number, since it uses as much as digits as its factorization.

268689991 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 3359232, while the sum is 58.

The square root of 268689991 is about 16391.7659512330. The cubic root of 268689991 is about 645.2834048925.

The spelling of 268689991 in words is "two hundred sixty-eight million, six hundred eighty-nine thousand, nine hundred ninety-one".