161361689 has 2 divisors, whose sum is σ = 161361690. Its totient is φ = 161361688.

The previous prime is 161361677. The next prime is 161361709. The reversal of 161361689 is 986163161.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 105411289 + 55950400 = 10267^2 + 7480^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-161361689 is a prime.

It is a Chen prime.

It is not a weakly prime, because it can be changed into another prime (161361619) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 80680844 + 80680845.

It is an arithmetic number, because the mean of its divisors is an integer number (80680845).

Almost surely, 2^161361689 is an apocalyptic number.

It is an amenable number.

161361689 is a deficient number, since it is larger than the sum of its proper divisors (1).

161361689 is an equidigital number, since it uses as much as digits as its factorization.

161361689 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 46656, while the sum is 41.

The square root of 161361689 is about 12702.8220880244. The cubic root of 161361689 is about 544.4192551337.

The spelling of 161361689 in words is "one hundred sixty-one million, three hundred sixty-one thousand, six hundred eighty-nine".