18752221 has 4 divisors (see below), whose sum is σ = 19739200. Its totient is φ = 17765244.

The previous prime is 18752191. The next prime is 18752231. The reversal of 18752221 is 12225781.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4.

It is a cyclic number.

It is not a de Polignac number, because 18752221 - 2⁷ = 18752093 is a prime.

It is a Duffinian number.

It is a self number, because there is not a number n which added to its sum of digits gives 18752221.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (18752231) 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, 493461 + ... + 493498.

It is an arithmetic number, because the mean of its divisors is an integer number (4934800).

Almost surely, 2^18752221 is an apocalyptic number.

It is an amenable number.

18752221 is a deficient number, since it is larger than the sum of its proper divisors (986979).

18752221 is an equidigital number, since it uses as much as digits as its factorization.

18752221 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 986978.

The product of its digits is 2240, while the sum is 28.

The square root of 18752221 is about 4330.3834703176. The cubic root of 18752221 is about 265.6751315023.

It can be divided in two parts, 1875 and 2221, that added together give a 12-th power (4096 = 2¹²).

The spelling of 18752221 in words is "eighteen million, seven hundred fifty-two thousand, two hundred twenty-one".