16639921536 has 128 divisors (see below), whose sum is σ = 53172844800. Its totient is φ = 4504025088.

The previous prime is 16639921523. The next prime is 16639921537. The reversal of 16639921536 is 63512993661.

It is a happy number.

16639921536 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is a tau number, because it is divible by the number of its divisors (128).

It is a super-3 number, since 3×16639921536³ (a number of 32 digits) contains 333 as substring.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (16639921537) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 111835 + ... + 213978.

It is an arithmetic number, because the mean of its divisors is an integer number (415412850).

Almost surely, 2^16639921536 is an apocalyptic number.

16639921536 is a gapful number since it is divisible by the number (16) formed by its first and last digit.

It is an amenable number.

16639921536 is an abundant number, since it is smaller than the sum of its proper divisors (36532923264).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

16639921536 is a wasteful number, since it uses less digits than its factorization.

16639921536 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 325856 (or 325844 counting only the distinct ones).

The product of its digits is 1574640, while the sum is 51.

The spelling of 16639921536 in words is "sixteen billion, six hundred thirty-nine million, nine hundred twenty-one thousand, five hundred thirty-six".