18021726 has 24 divisors (see below), whose sum is σ = 40307904. Its totient is φ = 5813280.

The previous prime is 18021713. The next prime is 18021737. The reversal of 18021726 is 62712081.

It is a self number, because there is not a number n which added to its sum of digits gives 18021726.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 15591 + ... + 16706.

It is an arithmetic number, because the mean of its divisors is an integer number (1679496).

Almost surely, 2^18021726 is an apocalyptic number.

18021726 is an abundant number, since it is smaller than the sum of its proper divisors (22286178).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

18021726 is a wasteful number, since it uses less digits than its factorization.

18021726 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 32336 (or 32333 counting only the distinct ones).

The product of its (nonzero) digits is 1344, while the sum is 27.

The square root of 18021726 is about 4245.2003486290. The cubic root of 18021726 is about 262.1795381889.

The spelling of 18021726 in words is "eighteen million, twenty-one thousand, seven hundred twenty-six".