166215354625345 has 4 divisors (see below), whose sum is σ = 199458425550420. Its totient is φ = 132972283700272.

The previous prime is 166215354625303. The next prime is 166215354625357. The reversal of 166215354625345 is 543526453512661.

It is a semiprime because it is the product of two primes.

It can be written as a sum of positive squares in 2 ways, for example, as 130636121907456 + 35579232717889 = 11429616^2 + 5964833^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-166215354625345 is a prime.

It is a super-2 number, since 2×166215354625345² (a number of 29 digits) contains 22 as substring.

It is a Smith number, since the sum of its digits (58) coincides with the sum of the digits of its prime factors. Since it is squarefree, it is also a hoax number.

It is a self number, because there is not a number n which added to its sum of digits gives 166215354625345.

It is an unprimeable number.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 16621535462530 + ... + 16621535462539.

It is an arithmetic number, because the mean of its divisors is an integer number (49864606387605).

Almost surely, 2^{166215354625345} is an apocalyptic number.

It is an amenable number.

166215354625345 is a deficient number, since it is larger than the sum of its proper divisors (33243070925075).

166215354625345 is an equidigital number, since it uses as much as digits as its factorization.

166215354625345 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 33243070925074.

The product of its digits is 77760000, while the sum is 58.

The spelling of 166215354625345 in words is "one hundred sixty-six trillion, two hundred fifteen billion, three hundred fifty-four million, six hundred twenty-five thousand, three hundred forty-five".