81541115 has 16 divisors (see below), whose sum is σ = 100590336. Its totient is φ = 63420000.

The previous prime is 81541111. The next prime is 81541121. The reversal of 81541115 is 51114518.

It is not a de Polignac number, because 81541115 - 2² = 81541111 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (81541111) 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, 53210 + ... + 54720.

It is an arithmetic number, because the mean of its divisors is an integer number (6286896).

Almost surely, 2^81541115 is an apocalyptic number.

81541115 is a deficient number, since it is larger than the sum of its proper divisors (19049221).

81541115 is a wasteful number, since it uses less digits than its factorization.

81541115 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1810.

The product of its digits is 800, while the sum is 26.

The square root of 81541115 is about 9030.0119047541. The cubic root of 81541115 is about 433.6362185532.

The spelling of 81541115 in words is "eighty-one million, five hundred forty-one thousand, one hundred fifteen".