15666505511660 has 12 divisors (see below), whose sum is σ = 32899661574528. Its totient is φ = 6266602204656.

The previous prime is 15666505511653. The next prime is 15666505511669. The reversal of 15666505511660 is 6611550566651.

It is not an unprimeable number, because it can be changed into a prime (15666505511669) 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, 391662637772 + ... + 391662637811.

It is an arithmetic number, because the mean of its divisors is an integer number (2741638464544).

Almost surely, 2^{15666505511660} is an apocalyptic number.

15666505511660 is a gapful number since it is divisible by the number (10) formed by its first and last digit.

It is an amenable number.

15666505511660 is an abundant number, since it is smaller than the sum of its proper divisors (17233156062868).

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

15666505511660 is a wasteful number, since it uses less digits than its factorization.

15666505511660 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 783325275592 (or 783325275590 counting only the distinct ones).

The product of its (nonzero) digits is 4860000, while the sum is 53.

The spelling of 15666505511660 in words is "fifteen trillion, six hundred sixty-six billion, five hundred five million, five hundred eleven thousand, six hundred sixty".