81457125 has 16 divisors (see below), whose sum is σ = 135545280. Its totient is φ = 43443600.

The previous prime is 81457097. The next prime is 81457127. The reversal of 81457125 is 52175418.

It is not a de Polignac number, because 81457125 - 2⁷ = 81456997 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (81457127) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 108235 + ... + 108984.

It is an arithmetic number, because the mean of its divisors is an integer number (8471580).

Almost surely, 2^81457125 is an apocalyptic number.

It is an amenable number.

81457125 is a deficient number, since it is larger than the sum of its proper divisors (54088155).

81457125 is a wasteful number, since it uses less digits than its factorization.

81457125 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 217237 (or 217227 counting only the distinct ones).

The product of its digits is 11200, while the sum is 33.

The square root of 81457125 is about 9025.3601036191. The cubic root of 81457125 is about 433.4872809360.

The spelling of 81457125 in words is "eighty-one million, four hundred fifty-seven thousand, one hundred twenty-five".