206664431 has 2 divisors, whose sum is σ = 206664432. Its totient is φ = 206664430.

The previous prime is 206664413. The next prime is 206664449. The reversal of 206664431 is 134466602.

Together with previous prime (206664413) it forms an Ormiston pair, because they use the same digits, order apart.

It is a balanced prime because it is at equal distance from previous prime (206664413) and next prime (206664449).

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-206664431 is a prime.

It is a super-2 number, since 2×206664431² = 85420374081107522, which contains 22 as substring.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (206664481) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 103332215 + 103332216.

It is an arithmetic number, because the mean of its divisors is an integer number (103332216).

Almost surely, 2^206664431 is an apocalyptic number.

206664431 is a deficient number, since it is larger than the sum of its proper divisors (1).

206664431 is an equidigital number, since it uses as much as digits as its factorization.

206664431 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 20736, while the sum is 32.

The square root of 206664431 is about 14375.8280109356. The cubic root of 206664431 is about 591.2283429321.

The spelling of 206664431 in words is "two hundred six million, six hundred sixty-four thousand, four hundred thirty-one".