161959501911 has 4 divisors (see below), whose sum is σ = 215946002552. Its totient is φ = 107973001272.

The previous prime is 161959501901. The next prime is 161959501931. The reversal of 161959501911 is 119105959161.

161959501911 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

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

It is not a de Polignac number, because 161959501911 - 2¹³ = 161959493719 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 (161959501901) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 26993250316 + ... + 26993250321.

It is an arithmetic number, because the mean of its divisors is an integer number (53986500638).

Almost surely, 2^161959501911 is an apocalyptic number.

161959501911 is a deficient number, since it is larger than the sum of its proper divisors (53986500641).

161959501911 is an equidigital number, since it uses as much as digits as its factorization.

161959501911 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 53986500640.

The product of its (nonzero) digits is 109350, while the sum is 48.

The spelling of 161959501911 in words is "one hundred sixty-one billion, nine hundred fifty-nine million, five hundred one thousand, nine hundred eleven".