201326591 has 4 divisors (see below), whose sum is σ = 201492432. Its totient is φ = 201160752.

The previous prime is 201326557. The next prime is 201326611. The reversal of 201326591 is 195623102.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 195623102 = 2 ⋅97811551.

It is a cyclic number.

It is not a de Polignac number, because 201326591 - 2¹⁰ = 201325567 is a prime.

It is a Duffinian number.

It is a plaindrome in base 4, base 8 and base 16.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (201326551) by changing a digit.

Being equal to 12×4¹²-1, it is a generalized Woodall number.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 81086 + ... + 83531.

It is an arithmetic number, because the mean of its divisors is an integer number (50373108).

Almost surely, 2^201326591 is an apocalyptic number.

201326591 is a deficient number, since it is larger than the sum of its proper divisors (165841).

201326591 is a wasteful number, since it uses less digits than its factorization.

201326591 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 165840.

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

The square root of 201326591 is about 14188.9601803656. The cubic root of 201326591 is about 586.0936912169.

Adding to 201326591 its reverse (195623102), we get a palindrome (396949693).

The spelling of 201326591 in words is "two hundred one million, three hundred twenty-six thousand, five hundred ninety-one".