16491768638 has 16 divisors (see below), whose sum is σ = 25453966176. Its totient is φ = 8010194400.

The previous prime is 16491768611. The next prime is 16491768641. The reversal of 16491768638 is 83686719461.

It is a congruent number.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (23) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 759506 + ... + 780917.

It is an arithmetic number, because the mean of its divisors is an integer number (1590872886).

Almost surely, 2^16491768638 is an apocalyptic number.

16491768638 is a deficient number, since it is larger than the sum of its proper divisors (8962197538).

16491768638 is a wasteful number, since it uses less digits than its factorization.

16491768638 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1540579.

The product of its digits is 10450944, while the sum is 59.

The spelling of 16491768638 in words is "sixteen billion, four hundred ninety-one million, seven hundred sixty-eight thousand, six hundred thirty-eight".