8209401821 has 8 divisors (see below), whose sum is σ = 8244156480. Its totient is φ = 8174688192.

The previous prime is 8209401727. The next prime is 8209401829. The reversal of 8209401821 is 1281049028.

8209401821 is digitally balanced in base 3, because in such base it contains all the possibile digits an equal number of times.

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

It is a de Polignac number, because none of the positive numbers 2^k-8209401821 is a prime.

It is a super-3 number, since 3×8209401821³ (a number of 31 digits) contains 333 as substring.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (8209401829) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 430160 + ... + 448838.

It is an arithmetic number, because the mean of its divisors is an integer number (1030519560).

Almost surely, 2^8209401821 is an apocalyptic number.

It is an amenable number.

8209401821 is a deficient number, since it is larger than the sum of its proper divisors (34754659).

8209401821 is a wasteful number, since it uses less digits than its factorization.

8209401821 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 20515.

The product of its (nonzero) digits is 9216, while the sum is 35.

The square root of 8209401821 is about 90605.7493815928. The cubic root of 8209401821 is about 2017.3000739881.

The spelling of 8209401821 in words is "eight billion, two hundred nine million, four hundred one thousand, eight hundred twenty-one".