205638143 has 2 divisors, whose sum is σ = 205638144. Its totient is φ = 205638142.

The previous prime is 205638133. The next prime is 205638151. The reversal of 205638143 is 341836502.

It is a strong prime.

It is a cyclic number.

It is not a de Polignac number, because 205638143 - 2²² = 201443839 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (205638133) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 102819071 + 102819072.

It is an arithmetic number, because the mean of its divisors is an integer number (102819072).

Almost surely, 2^205638143 is an apocalyptic number.

205638143 is a deficient number, since it is larger than the sum of its proper divisors (1).

205638143 is an equidigital number, since it uses as much as digits as its factorization.

205638143 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 17280, while the sum is 32.

The square root of 205638143 is about 14340.0886677872. The cubic root of 205638143 is about 590.2480456598.

The spelling of 205638143 in words is "two hundred five million, six hundred thirty-eight thousand, one hundred forty-three".