161178197 has 6 divisors (see below), whose sum is σ = 170108118. Its totient is φ = 152694792.

The previous prime is 161178187. The next prime is 161178203. The reversal of 161178197 is 791871161.

161178197 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It can be written as a sum of positive squares in only one way, i.e., 145106116 + 16072081 = 12046^2 + 4009^2 .

It is not a de Polignac number, because 161178197 - 2¹⁴ = 161161813 is a prime.

It is a super-2 number, since 2×161178197² = 51956822376341618, which contains 22 as substring.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (161178137) by changing a digit.

It is a polite number, since it can be written in 5 ways as a sum of consecutive naturals, for example, 222878 + ... + 223599.

It is an arithmetic number, because the mean of its divisors is an integer number (28351353).

Almost surely, 2^161178197 is an apocalyptic number.

It is an amenable number.

161178197 is a deficient number, since it is larger than the sum of its proper divisors (8929921).

161178197 is an equidigital number, since it uses as much as digits as its factorization.

161178197 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 446515 (or 446496 counting only the distinct ones).

The product of its digits is 21168, while the sum is 41.

The square root of 161178197 is about 12695.5975440308. The cubic root of 161178197 is about 544.2128152445.

The spelling of 161178197 in words is "one hundred sixty-one million, one hundred seventy-eight thousand, one hundred ninety-seven".