16321540447 has 4 divisors (see below), whose sum is σ = 16323818616. Its totient is φ = 16319262280.

The previous prime is 16321540441. The next prime is 16321540451. The reversal of 16321540447 is 74404512361.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 74404512361 = 313 ⋅237714097.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-16321540447 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (16321540441) 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, 1128304 + ... + 1142677.

It is an arithmetic number, because the mean of its divisors is an integer number (4080954654).

Almost surely, 2^16321540447 is an apocalyptic number.

16321540447 is a deficient number, since it is larger than the sum of its proper divisors (2278169).

16321540447 is an equidigital number, since it uses as much as digits as its factorization.

16321540447 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2278168.

The product of its (nonzero) digits is 80640, while the sum is 37.

The spelling of 16321540447 in words is "sixteen billion, three hundred twenty-one million, five hundred forty thousand, four hundred forty-seven".