81012881425 has 24 divisors (see below), whose sum is σ = 114878932992. Its totient is φ = 55516800000.

The previous prime is 81012881423. The next prime is 81012881441. The reversal of 81012881425 is 52418821018.

It is not a de Polignac number, because 81012881425 - 2¹ = 81012881423 is a prime.

It is a super-2 number, since 2×81012881425² (a number of 23 digits) contains 22 as substring.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (81012881423) 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 23 ways as a sum of consecutive naturals, for example, 135600 + ... + 424750.

It is an arithmetic number, because the mean of its divisors is an integer number (4786622208).

Almost surely, 2^81012881425 is an apocalyptic number.

It is an amenable number.

81012881425 is a deficient number, since it is larger than the sum of its proper divisors (33866051567).

81012881425 is a wasteful number, since it uses less digits than its factorization.

81012881425 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 290769 (or 290764 counting only the distinct ones).

The product of its (nonzero) digits is 40960, while the sum is 40.

The spelling of 81012881425 in words is "eighty-one billion, twelve million, eight hundred eighty-one thousand, four hundred twenty-five".