864969491 has 2 divisors, whose sum is σ = 864969492. Its totient is φ = 864969490.

The previous prime is 864969449. The next prime is 864969493. The reversal of 864969491 is 194969468.

864969491 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is a strong prime.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-864969491 is a prime.

Together with 864969493, it forms a pair of twin primes.

It is a Chen prime.

It is not a weakly prime, because it can be changed into another prime (864969493) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 432484745 + 432484746.

It is an arithmetic number, because the mean of its divisors is an integer number (432484746).

Almost surely, 2^864969491 is an apocalyptic number.

864969491 is a deficient number, since it is larger than the sum of its proper divisors (1).

864969491 is an equidigital number, since it uses as much as digits as its factorization.

864969491 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 3359232, while the sum is 56.

The square root of 864969491 is about 29410.3636665717. The cubic root of 864969491 is about 952.7967413123.

The spelling of 864969491 in words is "eight hundred sixty-four million, nine hundred sixty-nine thousand, four hundred ninety-one".