8819361821 has 8 divisors (see below), whose sum is σ = 8847497400. Its totient is φ = 8791257600.

The previous prime is 8819361797. The next prime is 8819361829. The reversal of 8819361821 is 1281639188.

It can be written as a sum of positive squares in 4 ways, for example, as 7579617721 + 1239744100 = 87061^2 + 35210^2 .

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 8819361821 - 2⁶ = 8819361757 is a prime.

It is a super-2 number, since 2×8819361821² (a number of 21 digits) contains 22 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 (8819361829) 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, 638375 + ... + 652043.

It is an arithmetic number, because the mean of its divisors is an integer number (1105937175).

Almost surely, 2^8819361821 is an apocalyptic number.

It is an amenable number.

8819361821 is a deficient number, since it is larger than the sum of its proper divisors (28135579).

8819361821 is a wasteful number, since it uses less digits than its factorization.

8819361821 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 15679.

The product of its digits is 165888, while the sum is 47.

The square root of 8819361821 is about 93911.4573468009. The cubic root of 8819361821 is about 2066.0732750284.

The spelling of 8819361821 in words is "eight billion, eight hundred nineteen million, three hundred sixty-one thousand, eight hundred twenty-one".