166204669397 has 4 divisors (see below), whose sum is σ = 178989643980. Its totient is φ = 153419694816.

The previous prime is 166204669289. The next prime is 166204669417. The reversal of 166204669397 is 793966402661.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 793966402661 = 14713 ⋅53963597.

It can be written as a sum of positive squares in 2 ways, for example, as 28425622801 + 137779046596 = 168599^2 + 371186^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-166204669397 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 (166204669597) 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, 6392487272 + ... + 6392487297.

It is an arithmetic number, because the mean of its divisors is an integer number (44747410995).

Almost surely, 2^166204669397 is an apocalyptic number.

It is an amenable number.

166204669397 is a deficient number, since it is larger than the sum of its proper divisors (12784974583).

166204669397 is a wasteful number, since it uses less digits than its factorization.

166204669397 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 12784974582.

The product of its (nonzero) digits is 17635968, while the sum is 59.

The spelling of 166204669397 in words is "one hundred sixty-six billion, two hundred four million, six hundred sixty-nine thousand, three hundred ninety-seven".