81766183825 has 12 divisors (see below), whose sum is σ = 101393831808. Its totient is φ = 65410518800.

The previous prime is 81766183777. The next prime is 81766183843. The reversal of 81766183825 is 52838166718.

It is not a de Polignac number, because 81766183825 - 2¹⁹ = 81765659537 is a prime.

It is a Duffinian number.

It is an unprimeable number.

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 11 ways as a sum of consecutive naturals, for example, 968040 + ... + 1049110.

It is an arithmetic number, because the mean of its divisors is an integer number (8449485984).

Almost surely, 2^81766183825 is an apocalyptic number.

It is an amenable number.

81766183825 is a deficient number, since it is larger than the sum of its proper divisors (19627647983).

81766183825 is a wasteful number, since it uses less digits than its factorization.

81766183825 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 121424 (or 121419 counting only the distinct ones).

The product of its digits is 3870720, while the sum is 55.

The spelling of 81766183825 in words is "eighty-one billion, seven hundred sixty-six million, one hundred eighty-three thousand, eight hundred twenty-five".