81148009 has 8 divisors (see below), whose sum is σ = 83198720. Its totient is φ = 79104816.

The previous prime is 81147973. The next prime is 81148019. The reversal of 81148009 is 90084118.

It is a sphenic number, since it is the product of 3 distinct primes.

It is a cyclic number.

It is not a de Polignac number, because 81148009 - 2⁹ = 81147497 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (81148019) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 24547 + ... + 27655.

It is an arithmetic number, because the mean of its divisors is an integer number (10399840).

Almost surely, 2^81148009 is an apocalyptic number.

It is an amenable number.

81148009 is a deficient number, since it is larger than the sum of its proper divisors (2050711).

81148009 is a wasteful number, since it uses less digits than its factorization.

81148009 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 3759.

The product of its (nonzero) digits is 2304, while the sum is 31.

The square root of 81148009 is about 9008.2189693635. The cubic root of 81148009 is about 432.9382489051.

The spelling of 81148009 in words is "eighty-one million, one hundred forty-eight thousand, nine".