8939311821 has 32 divisors (see below), whose sum is σ = 14457421440. Its totient is φ = 5413996800.

The previous prime is 8939311811. The next prime is 8939311873. The reversal of 8939311821 is 1281139398.

8939311821 is a `hidden beast` number, since 89 + 393 + 1 + 182 + 1 = 666.

It is not a de Polignac number, because 8939311821 - 2⁶ = 8939311757 is a prime.

It is a super-2 number, since 2×8939311821² (a number of 21 digits) contains 22 as substring.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (8939311811) by changing a digit.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 451551 + ... + 470931.

It is an arithmetic number, because the mean of its divisors is an integer number (451794420).

Almost surely, 2^8939311821 is an apocalyptic number.

It is an amenable number.

8939311821 is a deficient number, since it is larger than the sum of its proper divisors (5518109619).

8939311821 is a wasteful number, since it uses less digits than its factorization.

8939311821 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 20954 (or 20948 counting only the distinct ones).

The product of its digits is 93312, while the sum is 45.

The square root of 8939311821 is about 94547.9339858889. The cubic root of 8939311821 is about 2075.3978485990.

The spelling of 8939311821 in words is "eight billion, nine hundred thirty-nine million, three hundred eleven thousand, eight hundred twenty-one".