161181071 has 4 divisors (see below), whose sum is σ = 164929512. Its totient is φ = 157432632.

The previous prime is 161181049. The next prime is 161181107. The reversal of 161181071 is 170181161.

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

It is a de Polignac number, because none of the positive numbers 2^k-161181071 is a prime.

It is a Duffinian number.

It is a self number, because there is not a number n which added to its sum of digits gives 161181071.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (161181011) 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, 1874156 + ... + 1874241.

It is an arithmetic number, because the mean of its divisors is an integer number (41232378).

Almost surely, 2^161181071 is an apocalyptic number.

161181071 is a deficient number, since it is larger than the sum of its proper divisors (3748441).

161181071 is an equidigital number, since it uses as much as digits as its factorization.

161181071 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 3748440.

The product of its (nonzero) digits is 336, while the sum is 26.

The square root of 161181071 is about 12695.7107323694. The cubic root of 161181071 is about 544.2160498803.

The spelling of 161181071 in words is "one hundred sixty-one million, one hundred eighty-one thousand, seventy-one".