161816527 has 4 divisors (see below), whose sum is σ = 164559240. Its totient is φ = 159073816.

The previous prime is 161816519. The next prime is 161816561. The reversal of 161816527 is 725618161.

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

It is a cyclic number.

It is not a de Polignac number, because 161816527 - 2³ = 161816519 is a prime.

It is an alternating number because its digits alternate between odd and even.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (161816587) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 1371268 + ... + 1371385.

It is an arithmetic number, because the mean of its divisors is an integer number (41139810).

Almost surely, 2^161816527 is an apocalyptic number.

161816527 is a deficient number, since it is larger than the sum of its proper divisors (2742713).

161816527 is an equidigital number, since it uses as much as digits as its factorization.

161816527 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 2742712.

The product of its digits is 20160, while the sum is 37.

The square root of 161816527 is about 12720.7125193521. The cubic root of 161816527 is about 544.9303022281.

It can be divided in two parts, 1618 and 16527, that added together give a triangular number (18145 = T₁₉₀).

The spelling of 161816527 in words is "one hundred sixty-one million, eight hundred sixteen thousand, five hundred twenty-seven".