18221071 has 8 divisors (see below), whose sum is σ = 20035584. Its totient is φ = 16432920.

The previous prime is 18221041. The next prime is 18221081. The reversal of 18221071 is 17012281.

18221071 = 314² + 315² + ... + 440².

It is a sphenic number, since it is the product of 3 distinct primes.

It is a cyclic number.

It is not a de Polignac number, because 18221071 - 2¹³ = 18212879 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (18221041) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 5125 + ... + 7918.

It is an arithmetic number, because the mean of its divisors is an integer number (2504448).

Almost surely, 2^18221071 is an apocalyptic number.

18221071 is a gapful number since it is divisible by the number (11) formed by its first and last digit.

18221071 is a deficient number, since it is larger than the sum of its proper divisors (1814513).

18221071 is a wasteful number, since it uses less digits than its factorization.

18221071 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 13181.

The product of its (nonzero) digits is 224, while the sum is 22.

The square root of 18221071 is about 4268.6146464632. The cubic root of 18221071 is about 263.1426840254.

It can be divided in two parts, 182210 and 71, that added together give a palindrome (182281).

The spelling of 18221071 in words is "eighteen million, two hundred twenty-one thousand, seventy-one".