15660521020 has 12 divisors (see below), whose sum is σ = 32887094184. Its totient is φ = 6264208400.

The previous prime is 15660521011. The next prime is 15660521021. The reversal of 15660521020 is 2012506651.

15660521020 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is a self number, because there is not a number n which added to its sum of digits gives 15660521020.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (15660521021) 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 3 ways as a sum of consecutive naturals, for example, 391513006 + ... + 391513045.

It is an arithmetic number, because the mean of its divisors is an integer number (2740591182).

Almost surely, 2^15660521020 is an apocalyptic number.

15660521020 is a gapful number since it is divisible by the number (10) formed by its first and last digit.

It is an amenable number.

15660521020 is an abundant number, since it is smaller than the sum of its proper divisors (17226573164).

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

15660521020 is a wasteful number, since it uses less digits than its factorization.

15660521020 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 783026060 (or 783026058 counting only the distinct ones).

The product of its (nonzero) digits is 3600, while the sum is 28.

The spelling of 15660521020 in words is "fifteen billion, six hundred sixty million, five hundred twenty-one thousand, twenty".