8021216393 has 4 divisors (see below), whose sum is σ = 8031132180. Its totient is φ = 8011300608.

The previous prime is 8021216389. The next prime is 8021216419. The reversal of 8021216393 is 3936121208.

It is a semiprime because it is the product of two primes.

It can be written as a sum of positive squares in 2 ways, for example, as 6247795849 + 1773420544 = 79043^2 + 42112^2 .

It is a cyclic number.

It is not a de Polignac number, because 8021216393 - 2² = 8021216389 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (8021216323) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 4956680 + ... + 4958297.

It is an arithmetic number, because the mean of its divisors is an integer number (2007783045).

Almost surely, 2^8021216393 is an apocalyptic number.

It is an amenable number.

8021216393 is a deficient number, since it is larger than the sum of its proper divisors (9915787).

8021216393 is an equidigital number, since it uses as much as digits as its factorization.

8021216393 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 9915786.

The product of its (nonzero) digits is 15552, while the sum is 35.

The square root of 8021216393 is about 89561.2438111486. The cubic root of 8021216393 is about 2001.7664720789.

The spelling of 8021216393 in words is "eight billion, twenty-one million, two hundred sixteen thousand, three hundred ninety-three".