81351115 has 16 divisors (see below), whose sum is σ = 102187008. Its totient is φ = 62055136.

The previous prime is 81351113. The next prime is 81351133. The reversal of 81351115 is 51115318.

It is a cyclic number.

It is not a de Polignac number, because 81351115 - 2¹ = 81351113 is a prime.

It is a Duffinian number.

It is a self number, because there is not a number n which added to its sum of digits gives 81351115.

It is not an unprimeable number, because it can be changed into a prime (81351113) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 43122 + ... + 44968.

It is an arithmetic number, because the mean of its divisors is an integer number (6386688).

Almost surely, 2^81351115 is an apocalyptic number.

81351115 is a deficient number, since it is larger than the sum of its proper divisors (20835893).

81351115 is a wasteful number, since it uses less digits than its factorization.

81351115 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2258.

The product of its digits is 600, while the sum is 25.

The square root of 81351115 is about 9019.4852957361. The cubic root of 81351115 is about 433.2991495060.

The spelling of 81351115 in words is "eighty-one million, three hundred fifty-one thousand, one hundred fifteen".