81941025536 has 36 divisors (see below), whose sum is σ = 163581352704. Its totient is φ = 40965657600.

The previous prime is 81941025499. The next prime is 81941025557. The reversal of 81941025536 is 63552014918.

It is a happy number.

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 3 ways as a sum of consecutive naturals, for example, 3231146 + ... + 3256406.

It is an arithmetic number, because the mean of its divisors is an integer number (4543926464).

Almost surely, 2^81941025536 is an apocalyptic number.

It is an amenable number.

81941025536 is a deficient number, since it is larger than the sum of its proper divisors (81640327168).

81941025536 is a wasteful number, since it uses less digits than its factorization.

81941025536 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 37948 (or 37934 counting only the distinct ones).

The product of its (nonzero) digits is 259200, while the sum is 44.

The spelling of 81941025536 in words is "eighty-one billion, nine hundred forty-one million, twenty-five thousand, five hundred thirty-six".