11018991 has 4 divisors (see below), whose sum is σ = 14691992. Its totient is φ = 7345992.

The previous prime is 11018989. The next prime is 11019013. The reversal of 11018991 is 19981011.

It is a happy number.

11018991 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 19981011 = 3 ⋅6660337.

It is not a de Polignac number, because 11018991 - 2¹ = 11018989 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 (11018951) 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, 1836496 + ... + 1836501.

It is an arithmetic number, because the mean of its divisors is an integer number (3672998).

Almost surely, 2^11018991 is an apocalyptic number.

11018991 is a deficient number, since it is larger than the sum of its proper divisors (3673001).

11018991 is an equidigital number, since it uses as much as digits as its factorization.

11018991 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 3673000.

The product of its (nonzero) digits is 648, while the sum is 30.

The square root of 11018991 is about 3319.4865566831. The cubic root of 11018991 is about 222.5259221576.

The spelling of 11018991 in words is "eleven million, eighteen thousand, nine hundred ninety-one".