161945953 has 16 divisors (see below), whose sum is σ = 180859392. Its totient is φ = 144000000.

The previous prime is 161945939. The next prime is 161945957. The reversal of 161945953 is 359549161.

It is a cyclic number.

It is not a de Polignac number, because 161945953 - 2²⁵ = 128391521 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (161945957) 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 15 ways as a sum of consecutive naturals, for example, 100353 + ... + 101953.

It is an arithmetic number, because the mean of its divisors is an integer number (11303712).

Almost surely, 2^161945953 is an apocalyptic number.

161945953 is a gapful number since it is divisible by the number (13) formed by its first and last digit.

It is an amenable number.

161945953 is a deficient number, since it is larger than the sum of its proper divisors (18913439).

161945953 is a wasteful number, since it uses less digits than its factorization.

161945953 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1896.

The product of its digits is 145800, while the sum is 43.

The square root of 161945953 is about 12725.7987175658. The cubic root of 161945953 is about 545.0755477012.

The spelling of 161945953 in words is "one hundred sixty-one million, nine hundred forty-five thousand, nine hundred fifty-three".