11217851 has 4 divisors (see below), whose sum is σ = 11240400. Its totient is φ = 11195304.

The previous prime is 11217799. The next prime is 11217853. The reversal of 11217851 is 15871211.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 15871211 = 1621 ⋅9791.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-11217851 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 11217851.

It is not an unprimeable number, because it can be changed into a prime (11217853) 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, 10511 + ... + 11528.

It is an arithmetic number, because the mean of its divisors is an integer number (2810100).

Almost surely, 2^11217851 is an apocalyptic number.

11217851 is a deficient number, since it is larger than the sum of its proper divisors (22549).

11217851 is an equidigital number, since it uses as much as digits as its factorization.

11217851 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 22548.

The product of its digits is 560, while the sum is 26.

The square root of 11217851 is about 3349.3060475269. The cubic root of 11217851 is about 223.8565926793.

The spelling of 11217851 in words is "eleven million, two hundred seventeen thousand, eight hundred fifty-one".