12173821 has 8 divisors (see below), whose sum is σ = 13449600. Its totient is φ = 10926240.

The previous prime is 12173809. The next prime is 12173827. The reversal of 12173821 is 12837121.

It is a happy number.

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 12173821 - 2⁵ = 12173789 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 (12173827) 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, 6136 + ... + 7873.

It is an arithmetic number, because the mean of its divisors is an integer number (1681200).

Almost surely, 2^12173821 is an apocalyptic number.

12173821 is a gapful number since it is divisible by the number (11) formed by its first and last digit.

It is an amenable number.

12173821 is a deficient number, since it is larger than the sum of its proper divisors (1275779).

12173821 is a wasteful number, since it uses less digits than its factorization.

12173821 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 14099.

The product of its digits is 672, while the sum is 25.

The square root of 12173821 is about 3489.1003138345. The cubic root of 12173821 is about 230.0429724370.

The spelling of 12173821 in words is "twelve million, one hundred seventy-three thousand, eight hundred twenty-one".