705497809 has 2 divisors, whose sum is σ = 705497810. Its totient is φ = 705497808.

The previous prime is 705497789. The next prime is 705497831. The reversal of 705497809 is 908794507.

It is a happy number.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 627352209 + 78145600 = 25047^2 + 8840^2 .

It is an emirp because it is prime and its reverse (908794507) is a distict prime.

It is a cyclic number.

It is not a de Polignac number, because 705497809 - 2²¹ = 703400657 is a prime.

It is a Chen prime.

It is not a weakly prime, because it can be changed into another prime (705497609) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 352748904 + 352748905.

It is an arithmetic number, because the mean of its divisors is an integer number (352748905).

Almost surely, 2^705497809 is an apocalyptic number.

It is an amenable number.

705497809 is a deficient number, since it is larger than the sum of its proper divisors (1).

705497809 is an equidigital number, since it uses as much as digits as its factorization.

705497809 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 635040, while the sum is 49.

The square root of 705497809 is about 26561.2087262609. The cubic root of 705497809 is about 890.2224789935. Note that the first 3 decimals are identical.

The spelling of 705497809 in words is "seven hundred five million, four hundred ninety-seven thousand, eight hundred nine".