161396215913 has 4 divisors (see below), whose sum is σ = 164441427588. Its totient is φ = 158351004240.

The previous prime is 161396215909. The next prime is 161396215919. The reversal of 161396215913 is 319512693161.

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

It can be written as a sum of positive squares in 2 ways, for example, as 142350007849 + 19046208064 = 377293^2 + 138008^2 .

It is a cyclic number.

It is not a de Polignac number, because 161396215913 - 2² = 161396215909 is a prime.

It is a super-2 number, since 2×161396215913² (a number of 23 digits) contains 22 as substring.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (161396215919) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 1522605758 + ... + 1522605863.

It is an arithmetic number, because the mean of its divisors is an integer number (41110356897).

Almost surely, 2^161396215913 is an apocalyptic number.

It is an amenable number.

161396215913 is a deficient number, since it is larger than the sum of its proper divisors (3045211675).

161396215913 is an equidigital number, since it uses as much as digits as its factorization.

161396215913 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 3045211674.

The product of its digits is 262440, while the sum is 47.

The spelling of 161396215913 in words is "one hundred sixty-one billion, three hundred ninety-six million, two hundred fifteen thousand, nine hundred thirteen".