20100891 has 8 divisors (see below), whose sum is σ = 26839120. Its totient is φ = 13381632.

The previous prime is 20100889. The next prime is 20100893. The reversal of 20100891 is 19800102.

It is an interprime number because it is at equal distance from previous prime (20100889) and next prime (20100893).

It is a sphenic number, since it is the product of 3 distinct primes.

It is not a de Polignac number, because 20100891 - 2¹ = 20100889 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (20100893) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 2050 + ... + 6663.

It is an arithmetic number, because the mean of its divisors is an integer number (3354890).

Almost surely, 2^20100891 is an apocalyptic number.

20100891 is a deficient number, since it is larger than the sum of its proper divisors (6738229).

20100891 is an equidigital number, since it uses as much as digits as its factorization.

20100891 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 9485.

The product of its (nonzero) digits is 144, while the sum is 21.

The square root of 20100891 is about 4483.4017219072. The cubic root of 20100891 is about 271.8974301484.

Adding to 20100891 its reverse (19800102), we get a palindrome (39900993).

The spelling of 20100891 in words is "twenty million, one hundred thousand, eight hundred ninety-one".