2166716520505 has 8 divisors (see below), whose sum is σ = 2600386965000. Its totient is φ = 1733155122816.

The previous prime is 2166716520503. The next prime is 2166716520509. The reversal of 2166716520505 is 5050256176612.

It can be written as a sum of positive squares in 4 ways, for example, as 598203246096 + 1568513274409 = 773436^2 + 1252403^2 .

It is a sphenic number, since it is the product of 3 distinct primes.

It is a cyclic number.

It is not a de Polignac number, because 2166716520505 - 2¹ = 2166716520503 is a prime.

It is not an unprimeable number, because it can be changed into a prime (2166716520503) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (23) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 27217980 + ... + 27297469.

It is an arithmetic number, because the mean of its divisors is an integer number (325048370625).

Almost surely, 2^{2166716520505} is an apocalyptic number.

It is an amenable number.

2166716520505 is a deficient number, since it is larger than the sum of its proper divisors (433670444495).

2166716520505 is an equidigital number, since it uses as much as digits as its factorization.

2166716520505 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 54523403.

The product of its (nonzero) digits is 756000, while the sum is 46.

The spelling of 2166716520505 in words is "two trillion, one hundred sixty-six billion, seven hundred sixteen million, five hundred twenty thousand, five hundred five".