161869289 has 2 divisors, whose sum is σ = 161869290. Its totient is φ = 161869288.

The previous prime is 161869277. The next prime is 161869307. The reversal of 161869289 is 982968161.

It is a happy number.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 159643225 + 2226064 = 12635^2 + 1492^2 .

It is a cyclic number.

It is not a de Polignac number, because 161869289 - 2²⁰ = 160820713 is a prime.

It is a Chen prime.

It is not a weakly prime, because it can be changed into another prime (161869219) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 80934644 + 80934645.

It is an arithmetic number, because the mean of its divisors is an integer number (80934645).

Almost surely, 2^161869289 is an apocalyptic number.

It is an amenable number.

161869289 is a deficient number, since it is larger than the sum of its proper divisors (1).

161869289 is an equidigital number, since it uses as much as digits as its factorization.

161869289 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 373248, while the sum is 50.

The square root of 161869289 is about 12722.7862121471. The cubic root of 161869289 is about 544.9895225660.

It can be divided in two parts, 1618 and 69289, that added together give a palindrome (70907).

The spelling of 161869289 in words is "one hundred sixty-one million, eight hundred sixty-nine thousand, two hundred eighty-nine".