206090561 has 2 divisors, whose sum is σ = 206090562. Its totient is φ = 206090560.

The previous prime is 206090543. The next prime is 206090567. The reversal of 206090561 is 165090602.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 149915536 + 56175025 = 12244^2 + 7495^2 .

It is a cyclic number.

It is not a de Polignac number, because 206090561 - 2⁶ = 206090497 is a prime.

It is a Chen prime.

It is not a weakly prime, because it can be changed into another prime (206090567) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 103045280 + 103045281.

It is an arithmetic number, because the mean of its divisors is an integer number (103045281).

Almost surely, 2^206090561 is an apocalyptic number.

It is an amenable number.

206090561 is a deficient number, since it is larger than the sum of its proper divisors (1).

206090561 is an equidigital number, since it uses as much as digits as its factorization.

206090561 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 3240, while the sum is 29.

The square root of 206090561 is about 14355.8545896787. The cubic root of 206090561 is about 590.6805906486.

The spelling of 206090561 in words is "two hundred six million, ninety thousand, five hundred sixty-one".