161072661 has 4 divisors (see below), whose sum is σ = 214763552. Its totient is φ = 107381772.

The previous prime is 161072629. The next prime is 161072663. The reversal of 161072661 is 166270161.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4.

It is not a de Polignac number, because 161072661 - 2⁵ = 161072629 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (161072663) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 26845441 + ... + 26845446.

It is an arithmetic number, because the mean of its divisors is an integer number (53690888).

Almost surely, 2^161072661 is an apocalyptic number.

It is an amenable number.

161072661 is a deficient number, since it is larger than the sum of its proper divisors (53690891).

161072661 is an equidigital number, since it uses as much as digits as its factorization.

161072661 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 53690890.

The product of its (nonzero) digits is 3024, while the sum is 30.

The square root of 161072661 is about 12691.4404619807. The cubic root of 161072661 is about 544.0940097136.

The spelling of 161072661 in words is "one hundred sixty-one million, seventy-two thousand, six hundred sixty-one".