8161609197 has 32 divisors (see below), whose sum is σ = 12821536000. Its totient is φ = 4615640064.

The previous prime is 8161609189. The next prime is 8161609217. The reversal of 8161609197 is 7919061618.

It is not a de Polignac number, because 8161609197 - 2³ = 8161609189 is a prime.

It is a super-2 number, since 2×8161609197² (a number of 21 digits) contains 22 as substring.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (8161609297) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 58929 + ... + 140697.

It is an arithmetic number, because the mean of its divisors is an integer number (400673000).

Almost surely, 2^8161609197 is an apocalyptic number.

It is an amenable number.

8161609197 is a deficient number, since it is larger than the sum of its proper divisors (4659926803).

8161609197 is an equidigital number, since it uses as much as digits as its factorization.

8161609197 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 81890 (or 81876 counting only the distinct ones).

The product of its (nonzero) digits is 163296, while the sum is 48.

The square root of 8161609197 is about 90341.6249411090. The cubic root of 8161609197 is about 2013.3777514548.

The spelling of 8161609197 in words is "eight billion, one hundred sixty-one million, six hundred nine thousand, one hundred ninety-seven".