18212505 has 8 divisors (see below), whose sum is σ = 29140032. Its totient is φ = 9713328.

The previous prime is 18212503. The next prime is 18212561. The reversal of 18212505 is 50521281.

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

It is not a de Polignac number, because 18212505 - 2¹ = 18212503 is a prime.

It is not an unprimeable number, because it can be changed into a prime (18212503) 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 7 ways as a sum of consecutive naturals, for example, 607069 + ... + 607098.

It is an arithmetic number, because the mean of its divisors is an integer number (3642504).

Almost surely, 2^18212505 is an apocalyptic number.

18212505 is a gapful number since it is divisible by the number (15) formed by its first and last digit.

It is an amenable number.

18212505 is a deficient number, since it is larger than the sum of its proper divisors (10927527).

18212505 is a wasteful number, since it uses less digits than its factorization.

18212505 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1214175.

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

The square root of 18212505 is about 4267.6111584820. The cubic root of 18212505 is about 263.1014417817.

Adding to 18212505 its reverse (50521281), we get a palindrome (68733786).

The spelling of 18212505 in words is "eighteen million, two hundred twelve thousand, five hundred five".