18505212 has 24 divisors (see below), whose sum is σ = 47104512. Its totient is φ = 5607600.

The previous prime is 18505189. The next prime is 18505229. The reversal of 18505212 is 21250581.

It is an alternating number because its digits alternate between odd and even.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 69964 + ... + 70227.

It is an arithmetic number, because the mean of its divisors is an integer number (1962688).

Almost surely, 2^18505212 is an apocalyptic number.

18505212 is a gapful number since it is divisible by the number (12) formed by its first and last digit.

It is an amenable number.

18505212 is an abundant number, since it is smaller than the sum of its proper divisors (28599300).

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

18505212 is a wasteful number, since it uses less digits than its factorization.

18505212 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 140209 (or 140207 counting only the distinct ones).

The product of its (nonzero) digits is 800, while the sum is 24.

The square root of 18505212 is about 4301.7684735467. The cubic root of 18505212 is about 264.5034584663.

Adding to 18505212 its reverse (21250581), we get a palindrome (39755793).

The spelling of 18505212 in words is "eighteen million, five hundred five thousand, two hundred twelve".