15666005555061 has 64 divisors (see below), whose sum is σ = 23279310544896. Its totient is φ = 9320664038400.

The previous prime is 15666005554949. The next prime is 15666005555077. The reversal of 15666005555061 is 16055550066651.

It is not a de Polignac number, because 15666005555061 - 2¹¹ = 15666005553013 is a prime.

It is a super-2 number, since 2×15666005555061² (a number of 27 digits) contains 22 as substring.

It is a Harshad number since it is a multiple of its sum of digits (51).

It is a junction number, because it is equal to n+sod(n) for n = 15666005554995 and 15666005555013.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (15666005553061) by changing a digit.

It is a polite number, since it can be written in 63 ways as a sum of consecutive naturals, for example, 79274706 + ... + 79472076.

It is an arithmetic number, because the mean of its divisors is an integer number (363739227264).

Almost surely, 2^{15666005555061} is an apocalyptic number.

It is an amenable number.

15666005555061 is a deficient number, since it is larger than the sum of its proper divisors (7613304989835).

15666005555061 is a wasteful number, since it uses less digits than its factorization.

15666005555061 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 198002.

The product of its (nonzero) digits is 4050000, while the sum is 51.

The spelling of 15666005555061 in words is "fifteen trillion, six hundred sixty-six billion, five million, five hundred fifty-five thousand, sixty-one".