213005785 has 4 divisors (see below), whose sum is σ = 255606948. Its totient is φ = 170404624.

The previous prime is 213005777. The next prime is 213005813. The reversal of 213005785 is 587500312.

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 46621584 + 166384201 = 6828^2 + 12899^2 .

It is a cyclic number.

It is not a de Polignac number, because 213005785 - 2³ = 213005777 is a prime.

It is a Smith number, since the sum of its digits (31) coincides with the sum of the digits of its prime factors. Since it is squarefree, it is also a hoax number.

It is a Duffinian number.

It is an unprimeable number.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 21300574 + ... + 21300583.

It is an arithmetic number, because the mean of its divisors is an integer number (63901737).

Almost surely, 2^213005785 is an apocalyptic number.

It is an amenable number.

213005785 is a deficient number, since it is larger than the sum of its proper divisors (42601163).

213005785 is an equidigital number, since it uses as much as digits as its factorization.

213005785 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 42601162.

The product of its (nonzero) digits is 8400, while the sum is 31.

The square root of 213005785 is about 14594.7177088151. The cubic root of 213005785 is about 597.2146685934.

The spelling of 213005785 in words is "two hundred thirteen million, five thousand, seven hundred eighty-five".