705447521 has 4 divisors (see below), whose sum is σ = 746944452. Its totient is φ = 663950592.

The previous prime is 705447451. The next prime is 705447571. The reversal of 705447521 is 125744507.

It is a semiprime because it is the product of two primes.

It can be written as a sum of positive squares in 2 ways, for example, as 523494400 + 181953121 = 22880^2 + 13489^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-705447521 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (705447571) 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 in 3 ways as a sum of consecutive naturals, for example, 20748440 + ... + 20748473.

It is an arithmetic number, because the mean of its divisors is an integer number (186736113).

Almost surely, 2^705447521 is an apocalyptic number.

It is an amenable number.

705447521 is a deficient number, since it is larger than the sum of its proper divisors (41496931).

705447521 is a wasteful number, since it uses less digits than its factorization.

705447521 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 41496930.

The product of its (nonzero) digits is 39200, while the sum is 35.

The square root of 705447521 is about 26560.2620657252. The cubic root of 705447521 is about 890.2013267560.

Adding to 705447521 its product of nonzero digits (39200), we get a square (705486721 = 26561²).

The spelling of 705447521 in words is "seven hundred five million, four hundred forty-seven thousand, five hundred twenty-one".