81548672569 has 32 divisors (see below), whose sum is σ = 102234746880. Its totient is φ = 63325281600.

The previous prime is 81548672501. The next prime is 81548672573. The reversal of 81548672569 is 96527684518.

It is not a de Polignac number, because 81548672569 - 2³³ = 72958737977 is a prime.

It is a super-2 number, since 2×81548672569² (a number of 23 digits) contains 22 as substring.

It is not an unprimeable number, because it can be changed into a prime (81548672069) by changing a digit.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 3375804 + ... + 3399874.

It is an arithmetic number, because the mean of its divisors is an integer number (3194835840).

Almost surely, 2^81548672569 is an apocalyptic number.

It is an amenable number.

81548672569 is a deficient number, since it is larger than the sum of its proper divisors (20686074311).

81548672569 is a wasteful number, since it uses less digits than its factorization.

81548672569 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 24781.

The product of its digits is 29030400, while the sum is 61.

The spelling of 81548672569 in words is "eighty-one billion, five hundred forty-eight million, six hundred seventy-two thousand, five hundred sixty-nine".