12015855 has 48 divisors (see below), whose sum is σ = 22407840. Its totient is φ = 5935104.

The previous prime is 12015811. The next prime is 12015863. The reversal of 12015855 is 55851021.

It is not a de Polignac number, because 12015855 - 2¹³ = 12007663 is a prime.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 47 ways as a sum of consecutive naturals, for example, 86376 + ... + 86514.

It is an arithmetic number, because the mean of its divisors is an integer number (466830).

Almost surely, 2^12015855 is an apocalyptic number.

12015855 is a gapful number since it is divisible by the number (15) formed by its first and last digit.

12015855 is a deficient number, since it is larger than the sum of its proper divisors (10391985).

12015855 is a wasteful number, since it uses less digits than its factorization.

12015855 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 280 (or 277 counting only the distinct ones).

The product of its (nonzero) digits is 2000, while the sum is 27.

The square root of 12015855 is about 3466.3893318553. The cubic root of 12015855 is about 229.0436343821.

Adding to 12015855 its reverse (55851021), we get a palindrome (67866876).

It can be divided in two parts, 1201 and 5855, that added together give a square (7056 = 84²).

The spelling of 12015855 in words is "twelve million, fifteen thousand, eight hundred fifty-five".