16363315921 has 4 divisors (see below), whose sum is σ = 16421548644. Its totient is φ = 16305083200.

The previous prime is 16363315909. The next prime is 16363315957. The reversal of 16363315921 is 12951336361.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 12951336361 = 53 ⋅244364837.

It can be written as a sum of positive squares in 2 ways, for example, as 7350661696 + 9012654225 = 85736^2 + 94935^2 .

It is a cyclic number.

It is not a de Polignac number, because 16363315921 - 2¹¹ = 16363313873 is a prime.

It is a Smith number, since the sum of its digits (40) coincides with the sum of the digits of its prime factors. Since it is squarefree, it is also a hoax number.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (16363310921) 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, 29115940 + ... + 29116501.

It is an arithmetic number, because the mean of its divisors is an integer number (4105387161).

Almost surely, 2^16363315921 is an apocalyptic number.

It is an amenable number.

16363315921 is a deficient number, since it is larger than the sum of its proper divisors (58232723).

16363315921 is an equidigital number, since it uses as much as digits as its factorization.

16363315921 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 58232722.

The product of its digits is 87480, while the sum is 40.

The spelling of 16363315921 in words is "sixteen billion, three hundred sixty-three million, three hundred fifteen thousand, nine hundred twenty-one".