205170661231 has 2 divisors, whose sum is σ = 205170661232. Its totient is φ = 205170661230.

The previous prime is 205170661217. The next prime is 205170661271. The reversal of 205170661231 is 132166071502.

It is a weak prime.

It is a cyclic number.

It is not a de Polignac number, because 205170661231 - 2⁹ = 205170660719 is a prime.

It is a super-2 number, since 2×205170661231² (a number of 23 digits) contains 22 as substring.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (205170661271) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 102585330615 + 102585330616.

It is an arithmetic number, because the mean of its divisors is an integer number (102585330616).

Almost surely, 2^205170661231 is an apocalyptic number.

205170661231 is a deficient number, since it is larger than the sum of its proper divisors (1).

205170661231 is an equidigital number, since it uses as much as digits as its factorization.

205170661231 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 15120, while the sum is 34.

The spelling of 205170661231 in words is "two hundred five billion, one hundred seventy million, six hundred sixty-one thousand, two hundred thirty-one".