161885525 has 12 divisors (see below), whose sum is σ = 201021732. Its totient is φ = 129325440.

The previous prime is 161885513. The next prime is 161885561. The reversal of 161885525 is 525588161.

161885525 = T₂₂₁ + T₂₂₂ + ... + T₉₉₃.

161885525 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It can be written as a sum of positive squares in 6 ways, for example, as 52432081 + 109453444 = 7241^2 + 10462^2 .

It is not a de Polignac number, because 161885525 - 2¹⁰ = 161884501 is a prime.

It is a Duffinian number.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 15137 + ... + 23513.

It is an arithmetic number, because the mean of its divisors is an integer number (16751811).

Almost surely, 2^161885525 is an apocalyptic number.

It is an amenable number.

161885525 is a deficient number, since it is larger than the sum of its proper divisors (39136207).

161885525 is an equidigital number, since it uses as much as digits as its factorization.

161885525 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 9160 (or 9155 counting only the distinct ones).

The product of its digits is 96000, while the sum is 41.

The square root of 161885525 is about 12723.4242639315. The cubic root of 161885525 is about 545.0077433459.

The spelling of 161885525 in words is "one hundred sixty-one million, eight hundred eighty-five thousand, five hundred twenty-five".