201591591 has 4 divisors (see below), whose sum is σ = 268788792. Its totient is φ = 134394392.

The previous prime is 201591583. The next prime is 201591659. The reversal of 201591591 is 195195102.

It is a happy number.

It is a semiprime because it is the product of two primes.

It is a cyclic number.

It is not a de Polignac number, because 201591591 - 2³ = 201591583 is a prime.

It is a super-2 number, since 2×201591591² = 81278339123822562, which contains 22 as substring.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (201591521) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 33598596 + ... + 33598601.

It is an arithmetic number, because the mean of its divisors is an integer number (67197198).

Almost surely, 2^201591591 is an apocalyptic number.

201591591 is a deficient number, since it is larger than the sum of its proper divisors (67197201).

201591591 is an equidigital number, since it uses as much as digits as its factorization.

201591591 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 67197200.

The product of its (nonzero) digits is 4050, while the sum is 33.

The square root of 201591591 is about 14198.2953554291. The cubic root of 201591591 is about 586.3507308390.

The spelling of 201591591 in words is "two hundred one million, five hundred ninety-one thousand, five hundred ninety-one".