81595089 has 9 divisors (see below), whose sum is σ = 117898729. Its totient is φ = 54378660.

The previous prime is 81595061. The next prime is 81595103. The reversal of 81595089 is 98059518.

The square root of 81595089 is 9033.

It is a perfect power (a square), and thus also a powerful number.

It is a tau number, because it is divible by the number of its divisors (9).

It is not a de Polignac number, because 81595089 - 2⁵ = 81595057 is a prime.

It is a Duffinian number.

It is a Curzon number.

It is not an unprimeable number, because it can be changed into a prime (81595039) by changing a digit.

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 8 ways as a sum of consecutive naturals, for example, 25594 + ... + 28604.

Almost surely, 2^81595089 is an apocalyptic number.

81595089 is the 9033-rd square number.

81595089 is the 4517-th centered octagonal number.

It is an amenable number.

81595089 is a deficient number, since it is larger than the sum of its proper divisors (36303640).

81595089 is an frugal number, since it uses more digits than its factorization.

81595089 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 6028 (or 3014 counting only the distinct ones).

The product of its (nonzero) digits is 129600, while the sum is 45.

The cubic root of 81595089 is about 433.7318754867.

Multiplying 81595089 by its product of nonzero digits (129600), we get a square (10574723534400 = 3251880²).

The spelling of 81595089 in words is "eighty-one million, five hundred ninety-five thousand, eighty-nine".