12101855 has 4 divisors (see below), whose sum is σ = 14522232. Its totient is φ = 9681480.

The previous prime is 12101839. The next prime is 12101857. The reversal of 12101855 is 55810121.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 55810121 = 23 ⋅2426527.

It is not a de Polignac number, because 12101855 - 2⁴ = 12101839 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 12101855.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (12101857) 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, 1210181 + ... + 1210190.

It is an arithmetic number, because the mean of its divisors is an integer number (3630558).

Almost surely, 2^12101855 is an apocalyptic number.

12101855 is a deficient number, since it is larger than the sum of its proper divisors (2420377).

12101855 is an equidigital number, since it uses as much as digits as its factorization.

12101855 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2420376.

The product of its (nonzero) digits is 400, while the sum is 23.

The square root of 12101855 is about 3478.7720534694. The cubic root of 12101855 is about 229.5887736967.

Adding to 12101855 its reverse (55810121), we get a palindrome (67911976).

The spelling of 12101855 in words is "twelve million, one hundred one thousand, eight hundred fifty-five".