10891111001 has 4 divisors (see below), whose sum is σ = 10904776932. Its totient is φ = 10877445072.

The previous prime is 10891110947. The next prime is 10891111003. The reversal of 10891111001 is 10011119801.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 10011119801 = 5209 ⋅1921889.

It can be written as a sum of positive squares in 2 ways, for example, as 3585135376 + 7305975625 = 59876^2 + 85475^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-10891111001 is a prime.

It is a super-2 number, since 2×10891111001² (a number of 21 digits) contains 22 as substring.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (10891111003) 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, 6831770 + ... + 6833363.

It is an arithmetic number, because the mean of its divisors is an integer number (2726194233).

Almost surely, 2^10891111001 is an apocalyptic number.

It is an amenable number.

10891111001 is a deficient number, since it is larger than the sum of its proper divisors (13665931).

10891111001 is an equidigital number, since it uses as much as digits as its factorization.

10891111001 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 13665930.

The product of its (nonzero) digits is 72, while the sum is 23.

The spelling of 10891111001 in words is "ten billion, eight hundred ninety-one million, one hundred eleven thousand, one".