161816854 has 4 divisors (see below), whose sum is σ = 242725284. Its totient is φ = 80908426.

The previous prime is 161816801. The next prime is 161816861. The reversal of 161816854 is 458618161.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 458618161 = 12647 ⋅36263.

It is a Smith number, since the sum of its digits (40) coincides with the sum of the digits of its prime factors. Since it is squarefree, it is also a hoax number.

It is a congruent number.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 40454212 + ... + 40454215.

It is an arithmetic number, because the mean of its divisors is an integer number (60681321).

Almost surely, 2^161816854 is an apocalyptic number.

161816854 is a deficient number, since it is larger than the sum of its proper divisors (80908430).

161816854 is an equidigital number, since it uses as much as digits as its factorization.

161816854 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 80908429.

The product of its digits is 46080, while the sum is 40.

The square root of 161816854 is about 12720.7253723992. The cubic root of 161816854 is about 544.9306692942.

The spelling of 161816854 in words is "one hundred sixty-one million, eight hundred sixteen thousand, eight hundred fifty-four".