20250191 has 4 divisors (see below), whose sum is σ = 21807912. Its totient is φ = 18692472.

The previous prime is 20250163. The next prime is 20250193. The reversal of 20250191 is 19105202.

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 20250191 - 2¹⁰ = 20249167 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 (20250193) 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, 778841 + ... + 778866.

It is an arithmetic number, because the mean of its divisors is an integer number (5451978).

Almost surely, 2^20250191 is an apocalyptic number.

20250191 is a deficient number, since it is larger than the sum of its proper divisors (1557721).

20250191 is a wasteful number, since it uses less digits than its factorization.

20250191 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1557720.

The product of its (nonzero) digits is 180, while the sum is 20.

The square root of 20250191 is about 4500.0212221722. The cubic root of 20250191 is about 272.5689458852.

Adding to 20250191 its reverse (19105202), we get a palindrome (39355393).

The spelling of 20250191 in words is "twenty million, two hundred fifty thousand, one hundred ninety-one".