2173804821 has 12 divisors (see below), whose sum is σ = 3141078720. Its totient is φ = 1448677800.

The previous prime is 2173804813. The next prime is 2173804859. The reversal of 2173804821 is 1284083712.

2173804821 is a `hidden beast` number, since 2 + 173 + 8 + 0 + 482 + 1 = 666.

It is not a de Polignac number, because 2173804821 - 2³ = 2173804813 is a prime.

It is a plaindrome in base 14.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (2173804861) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 16701 + ... + 68018.

It is an arithmetic number, because the mean of its divisors is an integer number (261756560).

Almost surely, 2^2173804821 is an apocalyptic number.

It is an amenable number.

2173804821 is a deficient number, since it is larger than the sum of its proper divisors (967273899).

2173804821 is a wasteful number, since it uses less digits than its factorization.

2173804821 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 87576 (or 87573 counting only the distinct ones).

The product of its (nonzero) digits is 21504, while the sum is 36.

The square root of 2173804821 is about 46624.0798407861. The cubic root of 2173804821 is about 1295.4088185172.

The spelling of 2173804821 in words is "two billion, one hundred seventy-three million, eight hundred four thousand, eight hundred twenty-one".