12505181 has 4 divisors (see below), whose sum is σ = 13467132. Its totient is φ = 11543232.

The previous prime is 12505151. The next prime is 12505189. The reversal of 12505181 is 18150521.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 18150521 = 2857 ⋅6353.

It can be written as a sum of positive squares in 2 ways, for example, as 6205081 + 6300100 = 2491^2 + 2510^2 .

It is a cyclic number.

It is not a de Polignac number, because 12505181 - 2⁶ = 12505117 is a prime.

It is a super-2 number, since 2×12505181² = 312759103685522, which contains 22 as substring.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (12505189) 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, 480956 + ... + 480981.

It is an arithmetic number, because the mean of its divisors is an integer number (3366783).

Almost surely, 2^12505181 is an apocalyptic number.

It is an amenable number.

12505181 is a deficient number, since it is larger than the sum of its proper divisors (961951).

12505181 is an equidigital number, since it uses as much as digits as its factorization.

12505181 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 961950.

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

The square root of 12505181 is about 3536.2665340723. The cubic root of 12505181 is about 232.1115013473. Note that the first 3 decimals are identical.

The spelling of 12505181 in words is "twelve million, five hundred five thousand, one hundred eighty-one".