81027413525 has 6 divisors (see below), whose sum is σ = 100473992802. Its totient is φ = 64821930800.

The previous prime is 81027413521. The next prime is 81027413543. The reversal of 81027413525 is 52531472018.

It can be written as a sum of positive squares in 3 ways, for example, as 6345361 + 81021068164 = 2519^2 + 284642^2 .

It is not a de Polignac number, because 81027413525 - 2² = 81027413521 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 (81027413521) 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 5 ways as a sum of consecutive naturals, for example, 1620548246 + ... + 1620548295.

It is an arithmetic number, because the mean of its divisors is an integer number (16745665467).

Almost surely, 2^81027413525 is an apocalyptic number.

It is an amenable number.

81027413525 is a deficient number, since it is larger than the sum of its proper divisors (19446579277).

81027413525 is a wasteful number, since it uses less digits than its factorization.

81027413525 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 3241096551 (or 3241096546 counting only the distinct ones).

The product of its (nonzero) digits is 67200, while the sum is 38.

The spelling of 81027413525 in words is "eighty-one billion, twenty-seven million, four hundred thirteen thousand, five hundred twenty-five".