12158817 has 12 divisors (see below), whose sum is σ = 17714736. Its totient is φ = 7356840.

The previous prime is 12158813. The next prime is 12158849. The reversal of 12158817 is 71885121.

12158817 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is not a de Polignac number, because 12158817 - 2² = 12158813 is a prime.

It is a Harshad number since it is a multiple of its sum of digits (33).

It is a nialpdrome in base 16.

It is not an unprimeable number, because it can be changed into a prime (12158813) by changing a digit.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 19728 + ... + 20334.

It is an arithmetic number, because the mean of its divisors is an integer number (1476228).

Almost surely, 2^12158817 is an apocalyptic number.

It is an amenable number.

12158817 is a deficient number, since it is larger than the sum of its proper divisors (5555919).

12158817 is an frugal number, since it uses more digits than its factorization.

12158817 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1228 (or 621 counting only the distinct ones).

The product of its digits is 4480, while the sum is 33.

The square root of 12158817 is about 3486.9495264486. The cubic root of 12158817 is about 229.9484257392.

Multiplying 12158817 by its sum of digits (33), we get a square (401240961 = 20031²).

12158817 divided by its sum of digits (33) gives a square (368449 = 607²).

The spelling of 12158817 in words is "twelve million, one hundred fifty-eight thousand, eight hundred seventeen".