161869489 has 2 divisors, whose sum is σ = 161869490. Its totient is φ = 161869488.

The previous prime is 161869483. The next prime is 161869541. The reversal of 161869489 is 984968161.

It is an a-pointer prime, because the next prime (161869541) can be obtained adding 161869489 to its sum of digits (52).

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 154579489 + 7290000 = 12433^2 + 2700^2 .

It is a cyclic number.

It is not a de Polignac number, because 161869489 - 2³ = 161869481 is a prime.

It is a super-2 number, since 2×161869489² = 52403462938242242, which contains 22 as substring.

It is not a weakly prime, because it can be changed into another prime (161869481) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 80934744 + 80934745.

It is an arithmetic number, because the mean of its divisors is an integer number (80934745).

Almost surely, 2^161869489 is an apocalyptic number.

It is an amenable number.

161869489 is a deficient number, since it is larger than the sum of its proper divisors (1).

161869489 is an equidigital number, since it uses as much as digits as its factorization.

161869489 is an evil number, because the sum of its binary digits is even.

The product of its digits is 746496, while the sum is 52.

The square root of 161869489 is about 12722.7940720582. The cubic root of 161869489 is about 544.9897470226.

The spelling of 161869489 in words is "one hundred sixty-one million, eight hundred sixty-nine thousand, four hundred eighty-nine".