11278891 has 6 divisors (see below), whose sum is σ = 12213420. Its totient is φ = 10411128.

The previous prime is 11278889. The next prime is 11278903. The reversal of 11278891 is 19887211.

It is not a de Polignac number, because 11278891 - 2¹ = 11278889 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 11278891.

It is not an unprimeable number, because it can be changed into a prime (11278801) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 5 ways as a sum of consecutive naturals, for example, 33201 + ... + 33538.

It is an arithmetic number, because the mean of its divisors is an integer number (2035570).

Almost surely, 2^11278891 is an apocalyptic number.

11278891 is a deficient number, since it is larger than the sum of its proper divisors (934529).

11278891 is an equidigital number, since it uses as much as digits as its factorization.

11278891 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 66765 (or 66752 counting only the distinct ones).

The product of its digits is 8064, while the sum is 37.

The square root of 11278891 is about 3358.4060207188. The cubic root of 11278891 is about 224.2618841283.

It can be divided in two parts, 112 and 78891, that added together give a triangular number (79003 = T₃₉₇).

The spelling of 11278891 in words is "eleven million, two hundred seventy-eight thousand, eight hundred ninety-one".