15666891936 has 48 divisors (see below), whose sum is σ = 41739423264. Its totient is φ = 5144350464.

The previous prime is 15666891917. The next prime is 15666891949. The reversal of 15666891936 is 63919866651.

It is a tau number, because it is divible by the number of its divisors (48).

It is a self number, because there is not a number n which added to its sum of digits gives 15666891936.

It is an unprimeable number.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 1211455 + ... + 1224318.

It is an arithmetic number, because the mean of its divisors is an integer number (869571318).

Almost surely, 2^15666891936 is an apocalyptic number.

15666891936 is a gapful number since it is divisible by the number (16) formed by its first and last digit.

It is an amenable number.

15666891936 is an abundant number, since it is smaller than the sum of its proper divisors (26072531328).

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

15666891936 is a wasteful number, since it uses less digits than its factorization.

15666891936 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2435853 (or 2435845 counting only the distinct ones).

The product of its digits is 12597120, while the sum is 60.

The spelling of 15666891936 in words is "fifteen billion, six hundred sixty-six million, eight hundred ninety-one thousand, nine hundred thirty-six".