20197161 has 16 divisors (see below), whose sum is σ = 30414720. Its totient is φ = 13242960.

The previous prime is 20197159. The next prime is 20197183. The reversal of 20197161 is 16179102.

It is not a de Polignac number, because 20197161 - 2¹ = 20197159 is a prime.

It is a Harshad number since it is a multiple of its sum of digits (27).

It is not an unprimeable number, because it can be changed into a prime (20197141) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 4485 + ... + 7778.

It is an arithmetic number, because the mean of its divisors is an integer number (1900920).

Almost surely, 2^20197161 is an apocalyptic number.

It is an amenable number.

20197161 is a deficient number, since it is larger than the sum of its proper divisors (10217559).

20197161 is a wasteful number, since it uses less digits than its factorization.

20197161 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 12333 (or 12327 counting only the distinct ones).

The product of its (nonzero) digits is 756, while the sum is 27.

The square root of 20197161 is about 4494.1251651462. The cubic root of 20197161 is about 272.3308087573.

It can be divided in two parts, 2019 and 7161, that added together give a triangular number (9180 = T₁₃₅).

The spelling of 20197161 in words is "twenty million, one hundred ninety-seven thousand, one hundred sixty-one".