16660642138 has 16 divisors (see below), whose sum is σ = 30064317120. Its totient is φ = 6764471136.

The previous prime is 16660642123. The next prime is 16660642151. The reversal of 16660642138 is 83124606661.

It is a happy number.

16660642138 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is a super-2 number, since 2×16660642138² (a number of 21 digits) contains 22 as substring.

It is a junction number, because it is equal to n+sod(n) for n = 16660642094 and 16660642103.

It is an unprimeable number.

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 7 ways as a sum of consecutive naturals, for example, 31316731 + ... + 31317262.

It is an arithmetic number, because the mean of its divisors is an integer number (1879019820).

Almost surely, 2^16660642138 is an apocalyptic number.

16660642138 is a deficient number, since it is larger than the sum of its proper divisors (13403674982).

16660642138 is a wasteful number, since it uses less digits than its factorization.

16660642138 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 62634021.

The product of its (nonzero) digits is 248832, while the sum is 43.

The spelling of 16660642138 in words is "sixteen billion, six hundred sixty million, six hundred forty-two thousand, one hundred thirty-eight".