201668539 has 2 divisors, whose sum is σ = 201668540. Its totient is φ = 201668538.

The previous prime is 201668497. The next prime is 201668561. The reversal of 201668539 is 935866102.

It is a strong prime.

It is a cyclic number.

It is not a de Polignac number, because 201668539 - 2²¹ = 199571387 is a prime.

It is not a weakly prime, because it can be changed into another prime (201668239) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 100834269 + 100834270.

It is an arithmetic number, because the mean of its divisors is an integer number (100834270).

Almost surely, 2^201668539 is an apocalyptic number.

201668539 is a deficient number, since it is larger than the sum of its proper divisors (1).

201668539 is an equidigital number, since it uses as much as digits as its factorization.

201668539 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 77760, while the sum is 40.

The square root of 201668539 is about 14201.0048588119. The cubic root of 201668539 is about 586.4253251816.

The spelling of 201668539 in words is "two hundred one million, six hundred sixty-eight thousand, five hundred thirty-nine".