81458321 has 4 divisors (see below), whose sum is σ = 93095232. Its totient is φ = 69821412.

The previous prime is 81458287. The next prime is 81458329. The reversal of 81458321 is 12385418.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4.

It is a cyclic number.

It is not a de Polignac number, because 81458321 - 2¹⁴ = 81441937 is a prime.

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

It is a Duffinian number.

It is a Curzon number.

It is not an unprimeable number, because it can be changed into a prime (81458329) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 5818445 + ... + 5818458.

It is an arithmetic number, because the mean of its divisors is an integer number (23273808).

Almost surely, 2^81458321 is an apocalyptic number.

It is an amenable number.

81458321 is a deficient number, since it is larger than the sum of its proper divisors (11636911).

81458321 is a wasteful number, since it uses less digits than its factorization.

81458321 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 11636910.

The product of its digits is 7680, while the sum is 32.

The square root of 81458321 is about 9025.4263611200. The cubic root of 81458321 is about 433.4894024948.

The spelling of 81458321 in words is "eighty-one million, four hundred fifty-eight thousand, three hundred twenty-one".