161802985 has 4 divisors (see below), whose sum is σ = 194163588. Its totient is φ = 129442384.

The previous prime is 161802973. The next prime is 161803013. The reversal of 161802985 is 589208161.

It is a semiprime because it is the product of two primes.

It can be written as a sum of positive squares in 2 ways, for example, as 81288256 + 80514729 = 9016^2 + 8973^2 .

It is a cyclic number.

It is not a de Polignac number, because 161802985 - 2¹³ = 161794793 is a prime.

It is a Smith number, since the sum of its digits (40) coincides with the sum of the digits of its prime factors. Since it is squarefree, it is also a hoax number.

It is a Duffinian number.

It is an unprimeable number.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 16180294 + ... + 16180303.

It is an arithmetic number, because the mean of its divisors is an integer number (48540897).

Almost surely, 2^161802985 is an apocalyptic number.

It is an amenable number.

161802985 is a deficient number, since it is larger than the sum of its proper divisors (32360603).

161802985 is an equidigital number, since it uses as much as digits as its factorization.

161802985 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 32360602.

The product of its (nonzero) digits is 34560, while the sum is 40.

The square root of 161802985 is about 12720.1802267106. The cubic root of 161802985 is about 544.9151005422.

The spelling of 161802985 in words is "one hundred sixty-one million, eight hundred two thousand, nine hundred eighty-five".