161981892158 has 8 divisors (see below), whose sum is σ = 245477713152. Its totient is φ = 80155987776.

The previous prime is 161981892151. The next prime is 161981892203. The reversal of 161981892158 is 851298189161.

It is a sphenic number, since it is the product of 3 distinct primes.

It is a junction number, because it is equal to n+sod(n) for n = 161981892097 and 161981892106.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (161981892151) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (23) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 417478910 + ... + 417479297.

It is an arithmetic number, because the mean of its divisors is an integer number (30684714144).

Almost surely, 2^161981892158 is an apocalyptic number.

161981892158 is a deficient number, since it is larger than the sum of its proper divisors (83495820994).

161981892158 is an equidigital number, since it uses as much as digits as its factorization.

161981892158 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 834958306.

The product of its digits is 2488320, while the sum is 59.

The spelling of 161981892158 in words is "one hundred sixty-one billion, nine hundred eighty-one million, eight hundred ninety-two thousand, one hundred fifty-eight".