206531431 has 2 divisors, whose sum is σ = 206531432. Its totient is φ = 206531430.

The previous prime is 206531411. The next prime is 206531443. The reversal of 206531431 is 134135602.

It is a strong prime.

It is a cyclic number.

It is not a de Polignac number, because 206531431 - 2⁵ = 206531399 is a prime.

It is a super-2 number, since 2×206531431² = 85310463981815522, which contains 22 as substring.

It is a junction number, because it is equal to n+sod(n) for n = 206531396 and 206531405.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (206531401) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 103265715 + 103265716.

It is an arithmetic number, because the mean of its divisors is an integer number (103265716).

Almost surely, 2^206531431 is an apocalyptic number.

206531431 is a deficient number, since it is larger than the sum of its proper divisors (1).

206531431 is an equidigital number, since it uses as much as digits as its factorization.

206531431 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 2160, while the sum is 25.

The square root of 206531431 is about 14371.2014459474. The cubic root of 206531431 is about 591.1014863276.

The spelling of 206531431 in words is "two hundred six million, five hundred thirty-one thousand, four hundred thirty-one".