81147019 has 8 divisors (see below), whose sum is σ = 83611712. Its totient is φ = 78719040.

The previous prime is 81146993. The next prime is 81147041. The reversal of 81147019 is 91074118.

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 81147019 - 2¹¹ = 81144971 is a prime.

It is a super-2 number, since 2×81147019² = 13169677385172722, which contains 22 as substring.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (81147049) 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, 4659 + ... + 13564.

It is an arithmetic number, because the mean of its divisors is an integer number (10451464).

Almost surely, 2^81147019 is an apocalyptic number.

81147019 is a deficient number, since it is larger than the sum of its proper divisors (2464693).

81147019 is a wasteful number, since it uses less digits than its factorization.

81147019 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 18357.

The product of its (nonzero) digits is 2016, while the sum is 31.

The square root of 81147019 is about 9008.1640193771. The cubic root of 81147019 is about 432.9364882925.

The spelling of 81147019 in words is "eighty-one million, one hundred forty-seven thousand, nineteen".