81281695 has 16 divisors (see below), whose sum is σ = 106593408. Its totient is φ = 59009440.

The previous prime is 81281687. The next prime is 81281713. The reversal of 81281695 is 59618218.

It is not a de Polignac number, because 81281695 - 2³ = 81281687 is a prime.

It is a Duffinian number.

It is a congruent number.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 44592 + ... + 46378.

It is an arithmetic number, because the mean of its divisors is an integer number (6662088).

Almost surely, 2^81281695 is an apocalyptic number.

81281695 is a deficient number, since it is larger than the sum of its proper divisors (25311713).

81281695 is a wasteful number, since it uses less digits than its factorization.

81281695 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 2630.

The product of its digits is 34560, while the sum is 40.

The square root of 81281695 is about 9015.6361395078. The cubic root of 81281695 is about 433.1758642175.

The spelling of 81281695 in words is "eighty-one million, two hundred eighty-one thousand, six hundred ninety-five".