161672805 has 144 divisors (see below), whose sum is σ = 364927680. Its totient is φ = 65608704.

The previous prime is 161672779. The next prime is 161672813. The reversal of 161672805 is 508276161.

It is not a de Polignac number, because 161672805 - 2⁷ = 161672677 is a prime.

It is a super-2 number, since 2×161672805² = 52276191753136050, which contains 22 as substring.

It is a Curzon number.

It is a self number, because there is not a number n which added to its sum of digits gives 161672805.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 143 ways as a sum of consecutive naturals, for example, 712102 + ... + 712328.

It is an arithmetic number, because the mean of its divisors is an integer number (2534220).

Almost surely, 2^161672805 is an apocalyptic number.

161672805 is a gapful number since it is divisible by the number (15) formed by its first and last digit.

It is an amenable number.

161672805 is an abundant number, since it is smaller than the sum of its proper divisors (203254875).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

161672805 is a wasteful number, since it uses less digits than its factorization.

161672805 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 288 (or 278 counting only the distinct ones).

The product of its (nonzero) digits is 20160, while the sum is 36.

The square root of 161672805 is about 12715.0621311891. The cubic root of 161672805 is about 544.7689226032.

The spelling of 161672805 in words is "one hundred sixty-one million, six hundred seventy-two thousand, eight hundred five".