161391895 has 16 divisors (see below), whose sum is σ = 222064128. Its totient is φ = 110305440.

The previous prime is 161391887. The next prime is 161391907. The reversal of 161391895 is 598193161.

It is not a de Polignac number, because 161391895 - 2³ = 161391887 is a prime.

It is a Duffinian number.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 3472 + ... + 18298.

It is an arithmetic number, because the mean of its divisors is an integer number (13879008).

Almost surely, 2^161391895 is an apocalyptic number.

161391895 is a deficient number, since it is larger than the sum of its proper divisors (60672233).

161391895 is a wasteful number, since it uses less digits than its factorization.

161391895 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 15150.

The product of its digits is 58320, while the sum is 43.

The square root of 161391895 is about 12704.0109807887. The cubic root of 161391895 is about 544.4532237543.

The spelling of 161391895 in words is "one hundred sixty-one million, three hundred ninety-one thousand, eight hundred ninety-five".