81075705 has 16 divisors (see below), whose sum is σ = 132482304. Its totient is φ = 42320000.

The previous prime is 81075697. The next prime is 81075733. The reversal of 81075705 is 50757018.

It is not a de Polignac number, because 81075705 - 2³ = 81075697 is a prime.

It is a super-3 number, since 3×81075705³ (a number of 25 digits) contains 333 as substring.

It is an unprimeable number.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 56796 + ... + 58205.

It is an arithmetic number, because the mean of its divisors is an integer number (8280144).

Almost surely, 2^81075705 is an apocalyptic number.

It is an amenable number.

81075705 is a deficient number, since it is larger than the sum of its proper divisors (51406599).

81075705 is a wasteful number, since it uses less digits than its factorization.

81075705 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 115056.

The product of its (nonzero) digits is 9800, while the sum is 33.

The square root of 81075705 is about 9004.2048510682. The cubic root of 81075705 is about 432.8096260371.

The spelling of 81075705 in words is "eighty-one million, seventy-five thousand, seven hundred five".