204645691 has 2 divisors, whose sum is σ = 204645692. Its totient is φ = 204645690.

The previous prime is 204645611. The next prime is 204645703. The reversal of 204645691 is 196546402.

204645691 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 not a de Polignac number, because 204645691 - 2⁷ = 204645563 is a prime.

It is a self number, because there is not a number n which added to its sum of digits gives 204645691.

It is not a weakly prime, because it can be changed into another prime (204645611) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 102322845 + 102322846.

It is an arithmetic number, because the mean of its divisors is an integer number (102322846).

Almost surely, 2^204645691 is an apocalyptic number.

204645691 is a deficient number, since it is larger than the sum of its proper divisors (1).

204645691 is an equidigital number, since it uses as much as digits as its factorization.

204645691 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 51840, while the sum is 37.

The square root of 204645691 is about 14305.4427054880. The cubic root of 204645691 is about 589.2969611231.

The spelling of 204645691 in words is "two hundred four million, six hundred forty-five thousand, six hundred ninety-one".