131220545 has 8 divisors (see below), whose sum is σ = 157648680. Its totient is φ = 104853760.

The previous prime is 131220539. The next prime is 131220553. The reversal of 131220545 is 545022131.

It can be written as a sum of positive squares in 4 ways, for example, as 3055504 + 128165041 = 1748^2 + 11321^2 .

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

It is not a de Polignac number, because 131220545 - 2¹⁶ = 131155009 is a prime.

It is a super-3 number, since 3×131220545³ (a number of 25 digits) contains 333 as substring.

It is a self number, because there is not a number n which added to its sum of digits gives 131220545.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 10490 + ... + 19299.

It is an arithmetic number, because the mean of its divisors is an integer number (19706085).

Almost surely, 2^131220545 is an apocalyptic number.

It is an amenable number.

131220545 is a deficient number, since it is larger than the sum of its proper divisors (26428135).

131220545 is an equidigital number, since it uses as much as digits as its factorization.

131220545 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 30675.

The product of its (nonzero) digits is 1200, while the sum is 23.

The square root of 131220545 is about 11455.1536436662. The cubic root of 131220545 is about 508.1601591128.

Adding to 131220545 its reverse (545022131), we get a palindrome (676242676).

The spelling of 131220545 in words is "one hundred thirty-one million, two hundred twenty thousand, five hundred forty-five".