131521545 has 24 divisors (see below), whose sum is σ = 231099336. Its totient is φ = 69182208.

The previous prime is 131521543. The next prime is 131521573. The reversal of 131521545 is 545125131.

131521545 is a `hidden beast` number, since 131 + 521 + 5 + 4 + 5 = 666.

It can be written as a sum of positive squares in 4 ways, for example, as 30338064 + 101183481 = 5508^2 + 10059^2 .

It is not a de Polignac number, because 131521545 - 2¹ = 131521543 is a prime.

It is not an unprimeable number, because it can be changed into a prime (131521541) by changing a digit.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 16734 + ... + 23303.

It is an arithmetic number, because the mean of its divisors is an integer number (9629139).

Almost surely, 2^131521545 is an apocalyptic number.

131521545 is a gapful number since it is divisible by the number (15) formed by its first and last digit.

It is an amenable number.

131521545 is a deficient number, since it is larger than the sum of its proper divisors (99577791).

131521545 is a wasteful number, since it uses less digits than its factorization.

131521545 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 40121 (or 40118 counting only the distinct ones).

The product of its digits is 3000, while the sum is 27.

The square root of 131521545 is about 11468.2843093464. The cubic root of 131521545 is about 508.5484098092.

Adding to 131521545 its reverse (545125131), we get a palindrome (676646676).

The spelling of 131521545 in words is "one hundred thirty-one million, five hundred twenty-one thousand, five hundred forty-five".