81458 has 12 divisors (see below), whose sum is σ = 132858. Its totient is φ = 37440.

The previous prime is 81457. The next prime is 81463. The reversal of 81458 is 85418.

It can be written as a sum of positive squares in 3 ways, for example, as 51529 + 29929 = 227^2 + 173^2 .

It is a Harshad number since it is a multiple of its sum of digits (26).

It is an alternating number because its digits alternate between even and odd.

Its product of digits (1280) is a multiple of the sum of its prime divisors (256).

It is a Curzon number.

It is not an unprimeable number, because it can be changed into a prime (81457) by changing a digit.

It is a polite number, since it can be written in 5 ways as a sum of consecutive naturals, for example, 218 + ... + 458.

2⁸¹⁴⁵⁸ is an apocalyptic number.

81458 is a deficient number, since it is larger than the sum of its proper divisors (51400).

81458 is a wasteful number, since it uses less digits than its factorization.

81458 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 269 (or 256 counting only the distinct ones).

The product of its digits is 1280, while the sum is 26.

The square root of 81458 is about 285.4084792013. The cubic root of 81458 is about 43.3488833082.

It can be divided in two parts, 8 and 1458, that multiplied together give a square (11664 = 108²).

The spelling of 81458 in words is "eighty-one thousand, four hundred fifty-eight".