197820161 has 8 divisors (see below), whose sum is σ = 246633024. Its totient is φ = 154145520.

The previous prime is 197820089. The next prime is 197820169. The reversal of 197820161 is 161028791.

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

It is a cyclic number.

It is not a de Polignac number, because 197820161 - 2²⁶ = 130711297 is a prime.

It is not an unprimeable number, because it can be changed into a prime (197820169) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 1284470 + ... + 1284623.

It is an arithmetic number, because the mean of its divisors is an integer number (30829128).

Almost surely, 2^197820161 is an apocalyptic number.

197820161 is a gapful number since it is divisible by the number (11) formed by its first and last digit.

It is an amenable number.

197820161 is a deficient number, since it is larger than the sum of its proper divisors (48812863).

197820161 is a wasteful number, since it uses less digits than its factorization.

197820161 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 2569111.

The product of its (nonzero) digits is 6048, while the sum is 35.

The square root of 197820161 is about 14064.8555271642. The cubic root of 197820161 is about 582.6711523442.

The spelling of 197820161 in words is "one hundred ninety-seven million, eight hundred twenty thousand, one hundred sixty-one".