161191008196 has 27 divisors (see below), whose sum is σ = 283801942669. Its totient is φ = 80107698608.

The previous prime is 161191008191. The next prime is 161191008239. The reversal of 161191008196 is 691800191161.

The square root of 161191008196 is 401486.

It is a perfect power (a square), and thus also a powerful number.

It can be written as a sum of positive squares in only one way, i.e., 157934708100 + 3256300096 = 397410^2 + 57064^2 .

It is a super-2 number, since 2×161191008196² (a number of 23 digits) contains 22 as substring.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (161191008191) by changing a digit.

It is a polite number, since it can be written in 8 ways as a sum of consecutive naturals, for example, 158184975 + ... + 158185993.

Almost surely, 2^161191008196 is an apocalyptic number.

161191008196 is the 401486-th square number.

It is an amenable number.

161191008196 is a deficient number, since it is larger than the sum of its proper divisors (122610934473).

161191008196 is an frugal number, since it uses more digits than its factorization.

161191008196 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 2436 (or 1218 counting only the distinct ones).

The product of its (nonzero) digits is 23328, while the sum is 43.

The spelling of 161191008196 in words is "one hundred sixty-one billion, one hundred ninety-one million, eight thousand, one hundred ninety-six".