209587161 has 24 divisors (see below), whose sum is σ = 329543904. Its totient is φ = 118117440.

The previous prime is 209587159. The next prime is 209587207. The reversal of 209587161 is 161785902.

It is not a de Polignac number, because 209587161 - 2¹ = 209587159 is a prime.

It is a hoax number, since the sum of its digits (39) coincides with the sum of the digits of its distinct prime factors.

It is not an unprimeable number, because it can be changed into a prime (209587141) by changing a digit.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 966 + ... + 20496.

It is an arithmetic number, because the mean of its divisors is an integer number (13730996).

Almost surely, 2^209587161 is an apocalyptic number.

209587161 is a gapful number since it is divisible by the number (21) formed by its first and last digit.

It is an amenable number.

209587161 is a deficient number, since it is larger than the sum of its proper divisors (119956743).

209587161 is a wasteful number, since it uses less digits than its factorization.

209587161 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 19621 (or 19614 counting only the distinct ones).

The product of its (nonzero) digits is 30240, while the sum is 39.

The square root of 209587161 is about 14477.1254398102. The cubic root of 209587161 is about 594.0024345489.

The spelling of 209587161 in words is "two hundred nine million, five hundred eighty-seven thousand, one hundred sixty-one".