166235886309 has 4 divisors (see below), whose sum is σ = 221647848416. Its totient is φ = 110823924204.

The previous prime is 166235886307. The next prime is 166235886317. The reversal of 166235886309 is 903688532661.

It is a happy number.

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, and also an emirpimes, since its reverse is a distinct semiprime: 903688532661 = 3 ⋅301229510887.

It is not a de Polignac number, because 166235886309 - 2¹ = 166235886307 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (166235886307) 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, 27705981049 + ... + 27705981054.

It is an arithmetic number, because the mean of its divisors is an integer number (55411962104).

Almost surely, 2^166235886309 is an apocalyptic number.

It is an amenable number.

166235886309 is a deficient number, since it is larger than the sum of its proper divisors (55411962107).

166235886309 is an equidigital number, since it uses as much as digits as its factorization.

166235886309 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 55411962106.

The product of its (nonzero) digits is 11197440, while the sum is 57.

The spelling of 166235886309 in words is "one hundred sixty-six billion, two hundred thirty-five million, eight hundred eighty-six thousand, three hundred nine".