12111540 has 48 divisors (see below), whose sum is σ = 38758272. Its totient is φ = 2768256.

The previous prime is 12111527. The next prime is 12111563. The reversal of 12111540 is 4511121.

It is a happy number.

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 (13) of ones.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 13999 + ... + 14838.

It is an arithmetic number, because the mean of its divisors is an integer number (807464).

Almost surely, 2^12111540 is an apocalyptic number.

12111540 is a gapful number since it is divisible by the number (10) formed by its first and last digit.

It is an amenable number.

12111540 is an abundant number, since it is smaller than the sum of its proper divisors (26646732).

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

12111540 is a wasteful number, since it uses less digits than its factorization.

12111540 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 28856 (or 28854 counting only the distinct ones).

The product of its (nonzero) digits is 40, while the sum is 15.

The square root of 12111540 is about 3480.1637892490. The cubic root of 12111540 is about 229.6500032732.

Adding to 12111540 its reverse (4511121), we get a palindrome (16622661).

The spelling of 12111540 in words is "twelve million, one hundred eleven thousand, five hundred forty".