18121606 has 4 divisors (see below), whose sum is σ = 27182412. Its totient is φ = 9060802.

The previous prime is 18121603. The next prime is 18121613. The reversal of 18121606 is 60612181.

It is a semiprime because it is the product of two primes.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (18121603) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 4530400 + ... + 4530403.

It is an arithmetic number, because the mean of its divisors is an integer number (6795603).

Almost surely, 2^18121606 is an apocalyptic number.

18121606 is a deficient number, since it is larger than the sum of its proper divisors (9060806).

18121606 is an equidigital number, since it uses as much as digits as its factorization.

18121606 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 9060805.

The product of its (nonzero) digits is 576, while the sum is 25.

The square root of 18121606 is about 4256.9479677346. The cubic root of 18121606 is about 262.6629965761.

Adding to 18121606 its reverse (60612181), we get a palindrome (78733787).

The spelling of 18121606 in words is "eighteen million, one hundred twenty-one thousand, six hundred six".