12138985 has 4 divisors (see below), whose sum is σ = 14566788. Its totient is φ = 9711184.

The previous prime is 12138983. The next prime is 12139007. The reversal of 12138985 is 58983121.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 58983121 = 139 ⋅424339.

It can be written as a sum of positive squares in 2 ways, for example, as 4460544 + 7678441 = 2112^2 + 2771^2 .

It is a cyclic number.

It is not a de Polignac number, because 12138985 - 2¹ = 12138983 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (12138983) 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, 1213894 + ... + 1213903.

It is an arithmetic number, because the mean of its divisors is an integer number (3641697).

Almost surely, 2^12138985 is an apocalyptic number.

It is an amenable number.

12138985 is a deficient number, since it is larger than the sum of its proper divisors (2427803).

12138985 is an equidigital number, since it uses as much as digits as its factorization.

12138985 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2427802.

The product of its digits is 17280, while the sum is 37.

The square root of 12138985 is about 3484.1046195544. The cubic root of 12138985 is about 229.8233362985.

The spelling of 12138985 in words is "twelve million, one hundred thirty-eight thousand, nine hundred eighty-five".