15861623827661 has 16 divisors (see below), whose sum is σ = 16744000128000. Its totient is φ = 14984042933808.

The previous prime is 15861623827607. The next prime is 15861623827669. The reversal of 15861623827661 is 16672832616851.

15861623827661 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-15861623827661 is a prime.

It is a super-2 number, since 2×15861623827661² (a number of 27 digits) contains 22 as substring.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 15861623827594 and 15861623827603.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (15861623827669) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 13745900 + ... + 14855066.

It is an arithmetic number, because the mean of its divisors is an integer number (1046500008000).

Almost surely, 2^{15861623827661} is an apocalyptic number.

It is an amenable number.

15861623827661 is a deficient number, since it is larger than the sum of its proper divisors (882376300339).

15861623827661 is a wasteful number, since it uses less digits than its factorization.

15861623827661 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1111328.

The product of its digits is 34836480, while the sum is 62.

The spelling of 15861623827661 in words is "fifteen trillion, eight hundred sixty-one billion, six hundred twenty-three million, eight hundred twenty-seven thousand, six hundred sixty-one".