11111280 has 80 divisors (see below), whose sum is σ = 35009664. Its totient is φ = 2914560.

The previous prime is 11111273. The next prime is 11111311. The reversal of 11111280 is 8211111.

It is a tau number, because it is divible by the number of its divisors (80).

It is a Harshad number since it is a multiple of its sum of digits (15).

It is a congruent number.

It is an unprimeable number.

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 15 ways as a sum of consecutive naturals, for example, 15735 + ... + 16425.

Almost surely, 2^11111280 is an apocalyptic number.

11111280 is a gapful number since it is divisible by the number (10) formed by its first and last digit.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 11111280, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (17504832).

11111280 is an abundant number, since it is smaller than the sum of its proper divisors (23898384).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

11111280 is a wasteful number, since it uses less digits than its factorization.

11111280 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 774 (or 768 counting only the distinct ones).

The product of its (nonzero) digits is 16, while the sum is 15.

The square root of 11111280 is about 3333.3586665704. The cubic root of 11111280 is about 223.1454472862.

Adding to 11111280 its reverse (8211111), we get a palindrome (19322391).

The spelling of 11111280 in words is "eleven million, one hundred eleven thousand, two hundred eighty".