161500061 has 4 divisors (see below), whose sum is σ = 161532000. Its totient is φ = 161468124.

The previous prime is 161500021. The next prime is 161500067. The reversal of 161500061 is 160005161.

It is a happy number.

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 a cyclic number.

It is not a de Polignac number, because 161500061 - 2¹⁴ = 161483677 is a prime.

It is a Duffinian number.

It is a Curzon number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (161500067) 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, 6521 + ... + 19118.

It is an arithmetic number, because the mean of its divisors is an integer number (40383000).

Almost surely, 2^161500061 is an apocalyptic number.

It is an amenable number.

161500061 is a deficient number, since it is larger than the sum of its proper divisors (31939).

161500061 is an equidigital number, since it uses as much as digits as its factorization.

161500061 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 31938.

The product of its (nonzero) digits is 180, while the sum is 20.

The square root of 161500061 is about 12708.2674271515. The cubic root of 161500061 is about 544.5748287371.

The spelling of 161500061 in words is "one hundred sixty-one million, five hundred thousand, sixty-one".