131544520021 has 4 divisors (see below), whose sum is σ = 131545321600. Its totient is φ = 131543718444.

The previous prime is 131544520013. The next prime is 131544520027. The reversal of 131544520021 is 120025445131.

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, and also a brilliant number, because the two primes have the same length, and also an emirpimes, since its reverse is a distinct semiprime: 120025445131 = 97 ⋅1237375723.

It is a cyclic number.

It is not a de Polignac number, because 131544520021 - 2³ = 131544520013 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (131544520027) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 55431 + ... + 515908.

It is an arithmetic number, because the mean of its divisors is an integer number (32886330400).

Almost surely, 2^131544520021 is an apocalyptic number.

It is an amenable number.

131544520021 is a deficient number, since it is larger than the sum of its proper divisors (801579).

131544520021 is an equidigital number, since it uses as much as digits as its factorization.

131544520021 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 801578.

The product of its (nonzero) digits is 4800, while the sum is 28.

Adding to 131544520021 its reverse (120025445131), we get a palindrome (251569965152).

The spelling of 131544520021 in words is "one hundred thirty-one billion, five hundred forty-four million, five hundred twenty thousand, twenty-one".