86021 has 6 divisors (see below), whose sum is σ = 93330. Its totient is φ = 79248.

The previous prime is 86017. The next prime is 86027. The reversal of 86021 is 12068.

86021 = T₆₈ + T₆₉ + ... + T₉₃.

It can be written as a sum of positive squares in 3 ways, for example, as 2500 + 83521 = 50^2 + 289^2 .

It is not a de Polignac number, because 86021 - 2² = 86017 is a prime.

It is a super-2 number, since 2×86021² = 14799224882, which contains 22 as substring.

It is a Duffinian number.

It is a zygodrome in base 3 and base 4.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (86027) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (5) of ones.

It is a polite number, since it can be written in 5 ways as a sum of consecutive naturals, for example, 86 + ... + 423.

It is an arithmetic number, because the mean of its divisors is an integer number (15555).

2⁸⁶⁰²¹ is an apocalyptic number.

It is an amenable number.

86021 is a deficient number, since it is larger than the sum of its proper divisors (7309).

86021 is a wasteful number, since it uses less digits than its factorization.

86021 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 535 (or 522 counting only the distinct ones).

The product of its (nonzero) digits is 96, while the sum is 17.

The square root of 86021 is about 293.2933684896. The cubic root of 86021 is about 44.1436421268.

Adding to 86021 its reverse (12068), we get a palindrome (98089).

The spelling of 86021 in words is "eighty-six thousand, twenty-one".