161812869 has 32 divisors (see below), whose sum is σ = 228925440. Its totient is φ = 101554752.

The previous prime is 161812853. The next prime is 161812883. The reversal of 161812869 is 968218161.

It is not a de Polignac number, because 161812869 - 2⁴ = 161812853 is a prime.

It is a super-2 number, since 2×161812869² = 52366809148022322, which contains 22 as substring.

It is a self number, because there is not a number n which added to its sum of digits gives 161812869.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (161812829) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 440724 + ... + 441090.

It is an arithmetic number, because the mean of its divisors is an integer number (7153920).

Almost surely, 2^161812869 is an apocalyptic number.

It is an amenable number.

161812869 is a deficient number, since it is larger than the sum of its proper divisors (67112571).

161812869 is a wasteful number, since it uses less digits than its factorization.

161812869 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 529.

The product of its digits is 41472, while the sum is 42.

The square root of 161812869 is about 12720.5687372853. The cubic root of 161812869 is about 544.9261959930.

The spelling of 161812869 in words is "one hundred sixty-one million, eight hundred twelve thousand, eight hundred sixty-nine".