20211191 has 32 divisors (see below), whose sum is σ = 27664896. Its totient is φ = 14256000.

The previous prime is 20211187. The next prime is 20211197. The reversal of 20211191 is 19111202.

It is not a de Polignac number, because 20211191 - 2² = 20211187 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (20211197) by changing a digit.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 60896 + ... + 61226.

It is an arithmetic number, because the mean of its divisors is an integer number (864528).

Almost surely, 2^20211191 is an apocalyptic number.

20211191 is a deficient number, since it is larger than the sum of its proper divisors (7453705).

20211191 is a wasteful number, since it uses less digits than its factorization.

20211191 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 423.

The product of its (nonzero) digits is 36, while the sum is 17.

The square root of 20211191 is about 4495.6858208732. The cubic root of 20211191 is about 272.3938525498.

Adding to 20211191 its reverse (19111202), we get a palindrome (39322393).

It can be divided in two parts, 202111 and 91, that added together give a palindrome (202202).

The spelling of 20211191 in words is "twenty million, two hundred eleven thousand, one hundred ninety-one".