81071015 has 8 divisors (see below), whose sum is σ = 98934480. Its totient is φ = 63757312.

The previous prime is 81071009. The next prime is 81071017. The reversal of 81071015 is 51017018.

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 81071015 - 2²² = 76876711 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (81071017) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 137114 + ... + 137703.

It is an arithmetic number, because the mean of its divisors is an integer number (12366810).

Almost surely, 2^81071015 is an apocalyptic number.

81071015 is a deficient number, since it is larger than the sum of its proper divisors (17863465).

81071015 is a wasteful number, since it uses less digits than its factorization.

81071015 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 274881.

The product of its (nonzero) digits is 280, while the sum is 23.

The square root of 81071015 is about 9003.9444134224. The cubic root of 81071015 is about 432.8012802723.

The spelling of 81071015 in words is "eighty-one million, seventy-one thousand, fifteen".