204309643 has 2 divisors, whose sum is σ = 204309644. Its totient is φ = 204309642.

The previous prime is 204309593. The next prime is 204309653. The reversal of 204309643 is 346903402.

It is a strong prime.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-204309643 is a prime.

It is not a weakly prime, because it can be changed into another prime (204309653) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 102154821 + 102154822.

It is an arithmetic number, because the mean of its divisors is an integer number (102154822).

Almost surely, 2^204309643 is an apocalyptic number.

204309643 is a deficient number, since it is larger than the sum of its proper divisors (1).

204309643 is an equidigital number, since it uses as much as digits as its factorization.

204309643 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 15552, while the sum is 31.

The square root of 204309643 is about 14293.6924200852. The cubic root of 204309643 is about 588.9742235514.

The spelling of 204309643 in words is "two hundred four million, three hundred nine thousand, six hundred forty-three".