205681897 has 8 divisors (see below), whose sum is σ = 216639360. Its totient is φ = 194737680.

The previous prime is 205681877. The next prime is 205681901. The reversal of 205681897 is 798186502.

It is a sphenic number, since it is the product of 3 distinct primes.

It is a cyclic number.

It is not a de Polignac number, because 205681897 - 2⁷ = 205681769 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (205681877) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 55647 + ... + 59227.

It is an arithmetic number, because the mean of its divisors is an integer number (27079920).

Almost surely, 2^205681897 is an apocalyptic number.

It is an amenable number.

205681897 is a deficient number, since it is larger than the sum of its proper divisors (10957463).

205681897 is a wasteful number, since it uses less digits than its factorization.

205681897 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 6623.

The product of its (nonzero) digits is 241920, while the sum is 46.

The square root of 205681897 is about 14341.6141699601. The cubic root of 205681897 is about 590.2899054062.

The spelling of 205681897 in words is "two hundred five million, six hundred eighty-one thousand, eight hundred ninety-seven".