161544531 has 16 divisors (see below), whose sum is σ = 220084128. Its totient is φ = 105369600.

The previous prime is 161544521. The next prime is 161544533. The reversal of 161544531 is 135445161.

It is a happy number.

161544531 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is a de Polignac number, because none of the positive numbers 2^k-161544531 is a prime.

It is a super-2 number, since 2×161544531² = 52193270992019922, which contains 22 as substring.

It is not an unprimeable number, because it can be changed into a prime (161544533) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 33811 + ... + 38291.

It is an arithmetic number, because the mean of its divisors is an integer number (13755258).

Almost surely, 2^161544531 is an apocalyptic number.

161544531 is a deficient number, since it is larger than the sum of its proper divisors (58539597).

161544531 is a wasteful number, since it uses less digits than its factorization.

161544531 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 4742.

The product of its digits is 7200, while the sum is 30.

The square root of 161544531 is about 12710.0169551421. The cubic root of 161544531 is about 544.6248081201.

Adding to 161544531 its reverse (135445161), we get a palindrome (296989692).

The spelling of 161544531 in words is "one hundred sixty-one million, five hundred forty-four thousand, five hundred thirty-one".