205030909439 has 4 divisors (see below), whose sum is σ = 205032666960. Its totient is φ = 205029151920.

The previous prime is 205030909429. The next prime is 205030909471. The reversal of 205030909439 is 934909030502.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 934909030502 = 2 ⋅467454515251.

It is a cyclic number.

It is not a de Polignac number, because 205030909439 - 2⁴ = 205030909423 is a prime.

It is a Duffinian number.

It is a self number, because there is not a number n which added to its sum of digits gives 205030909439.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (205030909429) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 690299 + ... + 941580.

It is an arithmetic number, because the mean of its divisors is an integer number (51258166740).

Almost surely, 2^205030909439 is an apocalyptic number.

205030909439 is a deficient number, since it is larger than the sum of its proper divisors (1757521).

205030909439 is a wasteful number, since it uses less digits than its factorization.

205030909439 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1757520.

The product of its (nonzero) digits is 262440, while the sum is 44.

The spelling of 205030909439 in words is "two hundred five billion, thirty million, nine hundred nine thousand, four hundred thirty-nine".