166365125535321 has 8 divisors (see below), whose sum is σ = 246466852644960. Its totient is φ = 110910083690196.

The previous prime is 166365125535317. The next prime is 166365125535377. The reversal of 166365125535321 is 123535521563661.

166365125535321 is a `hidden beast` number, since 1 + 6 + 6 + 3 + 6 + 5 + 12 + 553 + 53 + 21 = 666.

It is not a de Polignac number, because 166365125535321 - 2² = 166365125535317 is a prime.

It is not an unprimeable number, because it can be changed into a prime (166365125535821) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 3080835658035 + ... + 3080835658088.

It is an arithmetic number, because the mean of its divisors is an integer number (30808356580620).

Almost surely, 2^{166365125535321} is an apocalyptic number.

It is an amenable number.

166365125535321 is a deficient number, since it is larger than the sum of its proper divisors (80101727109639).

166365125535321 is an equidigital number, since it uses as much as digits as its factorization.

166365125535321 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 6161671316132 (or 6161671316126 counting only the distinct ones).

The product of its digits is 14580000, while the sum is 54.

The spelling of 166365125535321 in words is "one hundred sixty-six trillion, three hundred sixty-five billion, one hundred twenty-five million, five hundred thirty-five thousand, three hundred twenty-one".