12181257 has 24 divisors (see below), whose sum is σ = 19476288. Its totient is φ = 7274400.

The previous prime is 12181249. The next prime is 12181259. The reversal of 12181257 is 75218121.

It is not a de Polignac number, because 12181257 - 2³ = 12181249 is a prime.

It is a hoax number, since the sum of its digits (27) coincides with the sum of the digits of its distinct prime factors.

It is a self number, because there is not a number n which added to its sum of digits gives 12181257.

It is not an unprimeable number, because it can be changed into a prime (12181259) by changing a digit.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 6163 + ... + 7895.

It is an arithmetic number, because the mean of its divisors is an integer number (811512).

Almost surely, 2^12181257 is an apocalyptic number.

It is an amenable number.

12181257 is a deficient number, since it is larger than the sum of its proper divisors (7295031).

12181257 is a wasteful number, since it uses less digits than its factorization.

12181257 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1821 (or 1818 counting only the distinct ones).

The product of its digits is 1120, while the sum is 27.

The square root of 12181257 is about 3490.1657553761. The cubic root of 12181257 is about 230.0898011024.

Adding to 12181257 its reverse (75218121), we get a palindrome (87399378).

The spelling of 12181257 in words is "twelve million, one hundred eighty-one thousand, two hundred fifty-seven".