205983742 has 4 divisors (see below), whose sum is σ = 308975616. Its totient is φ = 102991870.

The previous prime is 205983737. The next prime is 205983749. The reversal of 205983742 is 247389502.

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

It is a Smith number, since the sum of its digits (40) coincides with the sum of the digits of its prime factors. Since it is squarefree, it is also a hoax number.

It is a junction number, because it is equal to n+sod(n) for n = 205983695 and 205983704.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (205983749) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 51495934 + ... + 51495937.

It is an arithmetic number, because the mean of its divisors is an integer number (77243904).

Almost surely, 2^205983742 is an apocalyptic number.

205983742 is a deficient number, since it is larger than the sum of its proper divisors (102991874).

205983742 is a wasteful number, since it uses less digits than its factorization.

205983742 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 102991873.

The product of its (nonzero) digits is 120960, while the sum is 40.

The square root of 205983742 is about 14352.1337089647. The cubic root of 205983742 is about 590.5785209339.

The spelling of 205983742 in words is "two hundred five million, nine hundred eighty-three thousand, seven hundred forty-two".