205692661 has 8 divisors (see below), whose sum is σ = 208044504. Its totient is φ = 203347200.

The previous prime is 205692637. The next prime is 205692667. The reversal of 205692661 is 166296502.

It can be written as a sum of positive squares in 4 ways, for example, as 25300900 + 180391761 = 5030^2 + 13431^2 .

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

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-205692661 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 205692661.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (205692667) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 95185 + ... + 97321.

It is an arithmetic number, because the mean of its divisors is an integer number (26005563).

Almost surely, 2^205692661 is an apocalyptic number.

It is an amenable number.

205692661 is a deficient number, since it is larger than the sum of its proper divisors (2351843).

205692661 is a wasteful number, since it uses less digits than its factorization.

205692661 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 3191.

The product of its (nonzero) digits is 38880, while the sum is 37.

The square root of 205692661 is about 14341.9894366158. The cubic root of 205692661 is about 590.3002024876.

The spelling of 205692661 in words is "two hundred five million, six hundred ninety-two thousand, six hundred sixty-one".