81617115 has 8 divisors (see below), whose sum is σ = 130587408. Its totient is φ = 43529120.

The previous prime is 81617113. The next prime is 81617131. The reversal of 81617115 is 51171618.

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

It is not a de Polignac number, because 81617115 - 2¹ = 81617113 is a prime.

It is a super-2 number, since 2×81617115² = 13322706921846450, which contains 22 as substring.

It is not an unprimeable number, because it can be changed into a prime (81617113) 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, 2720556 + ... + 2720585.

It is an arithmetic number, because the mean of its divisors is an integer number (16323426).

Almost surely, 2^81617115 is an apocalyptic number.

81617115 is a deficient number, since it is larger than the sum of its proper divisors (48970293).

81617115 is a wasteful number, since it uses less digits than its factorization.

81617115 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 5441149.

The product of its digits is 1680, while the sum is 30.

The square root of 81617115 is about 9034.2191140131. The cubic root of 81617115 is about 433.7708995624.

The spelling of 81617115 in words is "eighty-one million, six hundred seventeen thousand, one hundred fifteen".