11212811 has 4 divisors (see below), whose sum is σ = 11229912. Its totient is φ = 11195712.

The previous prime is 11212787. The next prime is 11212823. The reversal of 11212811 is 11821211.

It is a semiprime because it is the product of two primes.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-11212811 is a prime.

It is a Duffinian number.

It is a self number, because there is not a number n which added to its sum of digits gives 11212811.

It is not an unprimeable number, because it can be changed into a prime (11212511) 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, 7526 + ... + 8891.

It is an arithmetic number, because the mean of its divisors is an integer number (2807478).

Almost surely, 2^11212811 is an apocalyptic number.

11212811 is a deficient number, since it is larger than the sum of its proper divisors (17101).

11212811 is an equidigital number, since it uses as much as digits as its factorization.

11212811 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 17100.

The product of its digits is 32, while the sum is 17.

The square root of 11212811 is about 3348.5535683336. The cubic root of 11212811 is about 223.8230626019.

Subtracting 11212811 from its reverse (11821211), we obtain a square (608400 = 780²).

The spelling of 11212811 in words is "eleven million, two hundred twelve thousand, eight hundred eleven".