166842516851 has 4 divisors (see below), whose sum is σ = 166845249792. Its totient is φ = 166839783912.

The previous prime is 166842516803. The next prime is 166842516857. The reversal of 166842516851 is 158615248661.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 158615248661 = 347 ⋅457104463.

It is a cyclic number.

It is not a de Polignac number, because 166842516851 - 2¹⁴ = 166842500467 is a prime.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 166842516793 and 166842516802.

It is not an unprimeable number, because it can be changed into a prime (166842516857) 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, 1272755 + ... + 1397708.

It is an arithmetic number, because the mean of its divisors is an integer number (41711312448).

Almost surely, 2^166842516851 is an apocalyptic number.

166842516851 is a deficient number, since it is larger than the sum of its proper divisors (2732941).

166842516851 is an equidigital number, since it uses as much as digits as its factorization.

166842516851 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2732940.

The product of its digits is 2764800, while the sum is 53.

The spelling of 166842516851 in words is "one hundred sixty-six billion, eight hundred forty-two million, five hundred sixteen thousand, eight hundred fifty-one".