81548975 has 12 divisors (see below), whose sum is σ = 101311224. Its totient is φ = 65116320.

The previous prime is 81548953. The next prime is 81548989. The reversal of 81548975 is 57984518.

It is not a de Polignac number, because 81548975 - 2¹⁰ = 81547951 is a prime.

It is a hoax number, since the sum of its digits (47) coincides with the sum of the digits of its distinct prime factors.

It is a Duffinian number.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 11897 + ... + 17453.

It is an arithmetic number, because the mean of its divisors is an integer number (8442602).

Almost surely, 2^81548975 is an apocalyptic number.

81548975 is a deficient number, since it is larger than the sum of its proper divisors (19762249).

81548975 is a wasteful number, since it uses less digits than its factorization.

81548975 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 6154 (or 6149 counting only the distinct ones).

The product of its digits is 403200, while the sum is 47.

The square root of 81548975 is about 9030.4471096397. The cubic root of 81548975 is about 433.6501512839.

The spelling of 81548975 in words is "eighty-one million, five hundred forty-eight thousand, nine hundred seventy-five".