18012523 has 4 divisors (see below), whose sum is σ = 18317880. Its totient is φ = 17707168.

The previous prime is 18012499. The next prime is 18012541. The reversal of 18012523 is 32521081.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 32521081 = 331 ⋅98251.

It is a cyclic number.

It is not a de Polignac number, because 18012523 - 2²¹ = 15915371 is a prime.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 18012494 and 18012503.

It is not an unprimeable number, because it can be changed into a prime (18012583) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 152590 + ... + 152707.

It is an arithmetic number, because the mean of its divisors is an integer number (4579470).

Almost surely, 2^18012523 is an apocalyptic number.

18012523 is a deficient number, since it is larger than the sum of its proper divisors (305357).

18012523 is an equidigital number, since it uses as much as digits as its factorization.

18012523 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 305356.

The product of its (nonzero) digits is 480, while the sum is 22.

The square root of 18012523 is about 4244.1162802166. The cubic root of 18012523 is about 262.1349022659.

The spelling of 18012523 in words is "eighteen million, twelve thousand, five hundred twenty-three".