161231545 has 8 divisors (see below), whose sum is σ = 193560840. Its totient is φ = 128929920.

The previous prime is 161231531. The next prime is 161231569. The reversal of 161231545 is 545132161.

161231545 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It can be written as a sum of positive squares in 4 ways, for example, as 1183744 + 160047801 = 1088^2 + 12651^2 .

It is a sphenic number, since it is the product of 3 distinct primes.

It is not a de Polignac number, because 161231545 - 2¹⁹ = 160707257 is a prime.

It is a super-2 number, since 2×161231545² = 51991222206174050, which contains 22 as substring.

It is an unprimeable number.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 9415 + ... + 20275.

It is an arithmetic number, because the mean of its divisors is an integer number (24195105).

Almost surely, 2^161231545 is an apocalyptic number.

It is an amenable number.

161231545 is a deficient number, since it is larger than the sum of its proper divisors (32329295).

161231545 is a wasteful number, since it uses less digits than its factorization.

161231545 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 13835.

The product of its digits is 3600, while the sum is 28.

The square root of 161231545 is about 12697.6984134921. The cubic root of 161231545 is about 544.2728512031.

The spelling of 161231545 in words is "one hundred sixty-one million, two hundred thirty-one thousand, five hundred forty-five".