206123531 has 2 divisors, whose sum is σ = 206123532. Its totient is φ = 206123530.

The previous prime is 206123513. The next prime is 206123537. The reversal of 206123531 is 135321602.

Together with previous prime (206123513) it forms an Ormiston pair, because they use the same digits, order apart.

It is a strong prime.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-206123531 is a prime.

It is a super-2 number, since 2×206123531² = 84973820063815922, which contains 22 as substring.

It is a junction number, because it is equal to n+sod(n) for n = 206123497 and 206123506.

It is not a weakly prime, because it can be changed into another prime (206123537) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 103061765 + 103061766.

It is an arithmetic number, because the mean of its divisors is an integer number (103061766).

Almost surely, 2^206123531 is an apocalyptic number.

206123531 is a deficient number, since it is larger than the sum of its proper divisors (1).

206123531 is an equidigital number, since it uses as much as digits as its factorization.

206123531 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 1080, while the sum is 23.

The square root of 206123531 is about 14357.0028557495. The cubic root of 206123531 is about 590.7120876445.

The spelling of 206123531 in words is "two hundred six million, one hundred twenty-three thousand, five hundred thirty-one".