166516806719 has 4 divisors (see below), whose sum is σ = 166645194144. Its totient is φ = 166388419296.

The previous prime is 166516806697. The next prime is 166516806739. The reversal of 166516806719 is 917608615661.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 917608615661 = 487 ⋅1884206603.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-166516806719 is a prime.

It is a super-2 number, since 2×166516806719² (a number of 23 digits) contains 22 as substring.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (166516806739) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 64191767 + ... + 64194360.

It is an arithmetic number, because the mean of its divisors is an integer number (41661298536).

Almost surely, 2^166516806719 is an apocalyptic number.

166516806719 is a deficient number, since it is larger than the sum of its proper divisors (128387425).

166516806719 is a wasteful number, since it uses less digits than its factorization.

166516806719 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 128387424.

The product of its (nonzero) digits is 3265920, while the sum is 56.

The spelling of 166516806719 in words is "one hundred sixty-six billion, five hundred sixteen million, eight hundred six thousand, seven hundred nineteen".