20885191 has 4 divisors (see below), whose sum is σ = 21605400. Its totient is φ = 20164984.

The previous prime is 20885177. The next prime is 20885201. The reversal of 20885191 is 19158802.

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 20885191 - 2⁵ = 20885159 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (20885101) 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, 360061 + ... + 360118.

It is an arithmetic number, because the mean of its divisors is an integer number (5401350).

Almost surely, 2^20885191 is an apocalyptic number.

20885191 is a deficient number, since it is larger than the sum of its proper divisors (720209).

20885191 is an equidigital number, since it uses as much as digits as its factorization.

20885191 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 720208.

The product of its (nonzero) digits is 5760, while the sum is 34.

The square root of 20885191 is about 4570.0318379635. The cubic root of 20885191 is about 275.3887218948.

The spelling of 20885191 in words is "twenty million, eight hundred eighty-five thousand, one hundred ninety-one".