81559695 has 16 divisors (see below), whose sum is σ = 149137920. Its totient is φ = 37284384.

The previous prime is 81559661. The next prime is 81559747. The reversal of 81559695 is 59695518.

It is a happy number.

It is not a de Polignac number, because 81559695 - 2¹² = 81555599 is a prime.

It is a congruent number.

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, 388275 + ... + 388484.

It is an arithmetic number, because the mean of its divisors is an integer number (9321120).

Almost surely, 2^81559695 is an apocalyptic number.

81559695 is a deficient number, since it is larger than the sum of its proper divisors (67578225).

81559695 is a wasteful number, since it uses less digits than its factorization.

81559695 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 776774.

The product of its digits is 486000, while the sum is 48.

The square root of 81559695 is about 9031.0406377117. The cubic root of 81559695 is about 433.6691522418.

The spelling of 81559695 in words is "eighty-one million, five hundred fifty-nine thousand, six hundred ninety-five".