231561521451 has 48 divisors (see below), whose sum is σ = 376131974400. Its totient is φ = 136208039616.

The previous prime is 231561521449. The next prime is 231561521533. The reversal of 231561521451 is 154125165132.

231561521451 is a `hidden beast` number, since 2 + 3 + 1 + 56 + 152 + 1 + 451 = 666.

231561521451 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is not a de Polignac number, because 231561521451 - 2¹ = 231561521449 is a prime.

It is not an unprimeable number, because it can be changed into a prime (231561521351) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written in 47 ways as a sum of consecutive naturals, for example, 3896680 + ... + 3955658.

It is an arithmetic number, because the mean of its divisors is an integer number (7836082800).

Almost surely, 2^231561521451 is an apocalyptic number.

231561521451 is a deficient number, since it is larger than the sum of its proper divisors (144570452949).

231561521451 is a wasteful number, since it uses less digits than its factorization.

231561521451 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 60480 (or 60477 counting only the distinct ones).

The product of its digits is 36000, while the sum is 36.

Adding to 231561521451 its reverse (154125165132), we get a palindrome (385686686583).

The spelling of 231561521451 in words is "two hundred thirty-one billion, five hundred sixty-one million, five hundred twenty-one thousand, four hundred fifty-one".