161026209 has 12 divisors (see below), whose sum is σ = 232844196. Its totient is φ = 107235072.

The previous prime is 161026199. The next prime is 161026211. The reversal of 161026209 is 902620161.

161026209 is a `hidden beast` number, since 1 + 610 + 26 + 20 + 9 = 666.

It can be written as a sum of positive squares in 2 ways, for example, as 101304225 + 59721984 = 10065^2 + 7728^2 .

It is a de Polignac number, because none of the positive numbers 2^k-161026209 is a prime.

It is not an unprimeable number, because it can be changed into a prime (161026279) by changing a digit.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 364 + ... + 17949.

It is an arithmetic number, because the mean of its divisors is an integer number (19403683).

Almost surely, 2^161026209 is an apocalyptic number.

It is an amenable number.

161026209 is a deficient number, since it is larger than the sum of its proper divisors (71817987).

161026209 is a wasteful number, since it uses less digits than its factorization.

161026209 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 19296 (or 19293 counting only the distinct ones).

The product of its (nonzero) digits is 1296, while the sum is 27.

The square root of 161026209 is about 12689.6102777036. The cubic root of 161026209 is about 544.0417006402.

The spelling of 161026209 in words is "one hundred sixty-one million, twenty-six thousand, two hundred nine".