205401439 has 4 divisors (see below), whose sum is σ = 205521160. Its totient is φ = 205281720.

The previous prime is 205401433. The next prime is 205401481. The reversal of 205401439 is 934104502.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 934104502 = 2 ⋅467052251.

It is a cyclic number.

It is not a de Polignac number, because 205401439 - 2⁵ = 205401407 is a prime.

It is a super-2 number, since 2×205401439² = 84379502286541442, which contains 22 as substring.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (205401433) 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 in 3 ways as a sum of consecutive naturals, for example, 57249 + ... + 60730.

It is an arithmetic number, because the mean of its divisors is an integer number (51380290).

Almost surely, 2^205401439 is an apocalyptic number.

205401439 is a deficient number, since it is larger than the sum of its proper divisors (119721).

205401439 is a wasteful number, since it uses less digits than its factorization.

205401439 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 119720.

The product of its (nonzero) digits is 4320, while the sum is 28.

The square root of 205401439 is about 14331.8330648944. The cubic root of 205401439 is about 590.0214863381.

The spelling of 205401439 in words is "two hundred five million, four hundred one thousand, four hundred thirty-nine".