82421581 has 8 divisors (see below), whose sum is σ = 93824064. Its totient is φ = 71670720.

The previous prime is 82421561. The next prime is 82421587. The reversal of 82421581 is 18512428.

It is a sphenic number, since it is the product of 3 distinct primes.

It is a de Polignac number, because none of the positive numbers 2^k-82421581 is a prime.

It is a super-2 number, since 2×82421581² = 13586634029079122, which contains 22 as substring.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (82421587) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 162636 + ... + 163141.

It is an arithmetic number, because the mean of its divisors is an integer number (11728008).

Almost surely, 2^82421581 is an apocalyptic number.

It is an amenable number.

82421581 is a deficient number, since it is larger than the sum of its proper divisors (11402483).

82421581 is a wasteful number, since it uses less digits than its factorization.

82421581 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 325811.

The product of its digits is 5120, while the sum is 31.

The square root of 82421581 is about 9078.6332121085. The cubic root of 82421581 is about 435.1914091357.

The spelling of 82421581 in words is "eighty-two million, four hundred twenty-one thousand, five hundred eighty-one".