81071115 has 8 divisors (see below), whose sum is σ = 129713808. Its totient is φ = 43237920.

The previous prime is 81071077. The next prime is 81071129. The reversal of 81071115 is 51117018.

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

It is not a de Polignac number, because 81071115 - 2¹⁹ = 80546827 is a prime.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 2702356 + ... + 2702385.

It is an arithmetic number, because the mean of its divisors is an integer number (16214226).

Almost surely, 2^81071115 is an apocalyptic number.

81071115 is a deficient number, since it is larger than the sum of its proper divisors (48642693).

81071115 is a wasteful number, since it uses less digits than its factorization.

81071115 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 5404749.

The product of its (nonzero) digits is 280, while the sum is 24.

The square root of 81071115 is about 9003.9499665425. The cubic root of 81071115 is about 432.8014582238.

The spelling of 81071115 in words is "eighty-one million, seventy-one thousand, one hundred fifteen".