205218497 has 16 divisors (see below), whose sum is σ = 229623552. Its totient is φ = 181806720.

The previous prime is 205218493. The next prime is 205218499. The reversal of 205218497 is 794812502.

It is a cyclic number.

It is not a de Polignac number, because 205218497 - 2² = 205218493 is a prime.

It is a super-2 number, since 2×205218497² = 84229263021878018, which contains 22 as substring.

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 205218497.

It is not an unprimeable number, because it can be changed into a prime (205218493) 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 15 ways as a sum of consecutive naturals, for example, 142493 + ... + 143925.

It is an arithmetic number, because the mean of its divisors is an integer number (14351472).

Almost surely, 2^205218497 is an apocalyptic number.

It is an amenable number.

205218497 is a deficient number, since it is larger than the sum of its proper divisors (24405055).

205218497 is a wasteful number, since it uses less digits than its factorization.

205218497 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1768.

The product of its (nonzero) digits is 40320, while the sum is 38.

The square root of 205218497 is about 14325.4492774223. The cubic root of 205218497 is about 589.8462656047.

The spelling of 205218497 in words is "two hundred five million, two hundred eighteen thousand, four hundred ninety-seven".