81764120275 has 24 divisors (see below), whose sum is σ = 103085659040. Its totient is φ = 64324316160.

The previous prime is 81764120257. The next prime is 81764120281. The reversal of 81764120275 is 57202146718.

It is not a de Polignac number, because 81764120275 - 2⁹ = 81764119763 is a prime.

It is an unprimeable number.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 273346 + ... + 488104.

Almost surely, 2^81764120275 is an apocalyptic number.

81764120275 is a deficient number, since it is larger than the sum of its proper divisors (21321538765).

81764120275 is a wasteful number, since it uses less digits than its factorization.

81764120275 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 215023 (or 215018 counting only the distinct ones).

The product of its (nonzero) digits is 188160, while the sum is 43.

The spelling of 81764120275 in words is "eighty-one billion, seven hundred sixty-four million, one hundred twenty thousand, two hundred seventy-five".