205145531 has 4 divisors (see below), whose sum is σ = 205288752. Its totient is φ = 205002312.

The previous prime is 205145519. The next prime is 205145543. The reversal of 205145531 is 135541502.

It is a semiprime because it is the product of two primes.

It is an interprime number because it is at equal distance from previous prime (205145519) and next prime (205145543).

It is a cyclic number.

It is not a de Polignac number, because 205145531 - 2¹⁰ = 205144507 is a prime.

It is a super-2 number, since 2×205145531² = 84169377778543922, 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 205145531.

It is not an unprimeable number, because it can be changed into a prime (205145231) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 69440 + ... + 72333.

It is an arithmetic number, because the mean of its divisors is an integer number (51322188).

Almost surely, 2^205145531 is an apocalyptic number.

205145531 is a deficient number, since it is larger than the sum of its proper divisors (143221).

205145531 is a wasteful number, since it uses less digits than its factorization.

205145531 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 143220.

The product of its (nonzero) digits is 3000, while the sum is 26.

The square root of 205145531 is about 14322.9023245989. The cubic root of 205145531 is about 589.7763501648.

The spelling of 205145531 in words is "two hundred five million, one hundred forty-five thousand, five hundred thirty-one".