166865707009 has 4 divisors (see below), whose sum is σ = 166867398400. Its totient is φ = 166864015620.

The previous prime is 166865706983. The next prime is 166865707039. The reversal of 166865707009 is 900707568661.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4.

It is a cyclic number.

It is not a de Polignac number, because 166865707009 - 2⁷ = 166865706881 is a prime.

It is a super-2 number, since 2×166865707009² (a number of 23 digits) contains 22 as substring.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (166865707039) 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, 687897 + ... + 898294.

It is an arithmetic number, because the mean of its divisors is an integer number (41716849600).

Almost surely, 2^166865707009 is an apocalyptic number.

It is an amenable number.

166865707009 is a deficient number, since it is larger than the sum of its proper divisors (1691391).

166865707009 is a wasteful number, since it uses less digits than its factorization.

166865707009 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1691390.

The product of its (nonzero) digits is 3810240, while the sum is 55.

The spelling of 166865707009 in words is "one hundred sixty-six billion, eight hundred sixty-five million, seven hundred seven thousand, nine".