81025 has 12 divisors (see below), whose sum is σ = 115072. Its totient is φ = 55440.

The previous prime is 81023. The next prime is 81031. The reversal of 81025 is 52018.

It is a happy number.

It is not a de Polignac number, because 81025 - 2¹ = 81023 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (81023) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (7) of ones.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 57 + ... + 406.

2⁸¹⁰²⁵ is an apocalyptic number.

It is an amenable number.

81025 is a deficient number, since it is larger than the sum of its proper divisors (34047).

81025 is a wasteful number, since it uses less digits than its factorization.

81025 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 480 (or 475 counting only the distinct ones).

The product of its (nonzero) digits is 80, while the sum is 16.

The square root of 81025 is about 284.6489065498. The cubic root of 81025 is about 43.2719380389.

The spelling of 81025 in words is "eighty-one thousand, twenty-five".