161522545 has 4 divisors (see below), whose sum is σ = 193827060. Its totient is φ = 129218032.

The previous prime is 161522527. The next prime is 161522549. The reversal of 161522545 is 545225161.

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 114832656 + 46689889 = 10716^2 + 6833^2 .

It is a cyclic number.

It is not a de Polignac number, because 161522545 - 2²⁷ = 27304817 is a prime.

It is a Smith number, since the sum of its digits (31) coincides with the sum of the digits of its prime factors. Since it is squarefree, it is also a hoax number.

It is not an unprimeable number, because it can be changed into a prime (161522549) 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, 16152250 + ... + 16152259.

It is an arithmetic number, because the mean of its divisors is an integer number (48456765).

Almost surely, 2^161522545 is an apocalyptic number.

It is an amenable number.

161522545 is a deficient number, since it is larger than the sum of its proper divisors (32304515).

161522545 is an equidigital number, since it uses as much as digits as its factorization.

161522545 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 32304514.

The product of its digits is 12000, while the sum is 31.

The square root of 161522545 is about 12709.1520173456. The cubic root of 161522545 is about 544.6000994237.

The spelling of 161522545 in words is "one hundred sixty-one million, five hundred twenty-two thousand, five hundred forty-five".