161522593 has 4 divisors (see below), whose sum is σ = 171023940. Its totient is φ = 152021248.

The previous prime is 161522573. The next prime is 161522609. The reversal of 161522593 is 395225161.

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 64834704 + 96687889 = 8052^2 + 9833^2 .

It is a cyclic number.

It is not a de Polignac number, because 161522593 - 2⁵ = 161522561 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (161522573) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 4750648 + ... + 4750681.

It is an arithmetic number, because the mean of its divisors is an integer number (42755985).

Almost surely, 2^161522593 is an apocalyptic number.

It is an amenable number.

161522593 is a deficient number, since it is larger than the sum of its proper divisors (9501347).

161522593 is an equidigital number, since it uses as much as digits as its factorization.

161522593 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 9501346.

The product of its digits is 16200, while the sum is 34.

The square root of 161522593 is about 12709.1539057484. The cubic root of 161522593 is about 544.6001533704.

The spelling of 161522593 in words is "one hundred sixty-one million, five hundred twenty-two thousand, five hundred ninety-three".