161536805 has 8 divisors (see below), whose sum is σ = 205246872. Its totient is φ = 121627648.

The previous prime is 161536789. The next prime is 161536807. The reversal of 161536805 is 508635161.

It can be written as a sum of positive squares in 4 ways, for example, as 28111204 + 133425601 = 5302^2 + 11551^2 .

It is a sphenic number, since it is the product of 3 distinct primes.

It is a cyclic number.

It is not a de Polignac number, because 161536805 - 2⁴ = 161536789 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (161536807) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 950132 + ... + 950301.

It is an arithmetic number, because the mean of its divisors is an integer number (25655859).

Almost surely, 2^161536805 is an apocalyptic number.

It is an amenable number.

161536805 is a deficient number, since it is larger than the sum of its proper divisors (43710067).

161536805 is a wasteful number, since it uses less digits than its factorization.

161536805 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1900455.

The product of its (nonzero) digits is 21600, while the sum is 35.

The square root of 161536805 is about 12709.7130180032. The cubic root of 161536805 is about 544.6161256053.

The spelling of 161536805 in words is "one hundred sixty-one million, five hundred thirty-six thousand, eight hundred five".