201211591 has 12 divisors (see below), whose sum is σ = 234358920. Its totient is φ = 172248720.

The previous prime is 201211589. The next prime is 201211603. The reversal of 201211591 is 195112102.

It is not a de Polignac number, because 201211591 - 2¹ = 201211589 is a prime.

It is a super-2 number, since 2×201211591² = 80972208705502562, which contains 22 as substring.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (201211511) by changing a digit.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 45465 + ... + 49693.

It is an arithmetic number, because the mean of its divisors is an integer number (19529910).

Almost surely, 2^201211591 is an apocalyptic number.

201211591 is a deficient number, since it is larger than the sum of its proper divisors (33147329).

201211591 is an equidigital number, since it uses as much as digits as its factorization.

201211591 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 5214 (or 5207 counting only the distinct ones).

The product of its (nonzero) digits is 180, while the sum is 22.

The square root of 201211591 is about 14184.9071551420. The cubic root of 201211591 is about 585.9820755388.

Adding to 201211591 its reverse (195112102), we get a palindrome (396323693).

It can be divided in two parts, 20121 and 1591, that added together give a palindrome (21712).

The spelling of 201211591 in words is "two hundred one million, two hundred eleven thousand, five hundred ninety-one".