15606640106021 has 32 divisors (see below), whose sum is σ = 16414747614720. Its totient is φ = 14809946747904.

The previous prime is 15606640106011. The next prime is 15606640106027. The reversal of 15606640106021 is 12060104660651.

It is a happy number.

15606640106021 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-15606640106021 is a prime.

It is a Duffinian number.

It is a Curzon number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (15606640106027) by changing a digit.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 1386388625 + ... + 1386399881.

It is an arithmetic number, because the mean of its divisors is an integer number (512960862960).

Almost surely, 2^{15606640106021} is an apocalyptic number.

It is an amenable number.

15606640106021 is a deficient number, since it is larger than the sum of its proper divisors (808107508699).

15606640106021 is a wasteful number, since it uses less digits than its factorization.

15606640106021 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 12485.

The product of its (nonzero) digits is 51840, while the sum is 38.

Adding to 15606640106021 its reverse (12060104660651), we get a palindrome (27666744766672).

The spelling of 15606640106021 in words is "fifteen trillion, six hundred six billion, six hundred forty million, one hundred six thousand, twenty-one".