248821 has 2 divisors, whose sum is σ = 248822. Its totient is φ = 248820.

The previous prime is 248813. The next prime is 248827. The reversal of 248821 is 128842.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 152100 + 96721 = 390^2 + 311^2 .

It is a cyclic number.

It is not a de Polignac number, because 248821 - 2³ = 248813 is a prime.

It is equal to p₂₁₉₄₉ and since 248821 and 21949 have the same sum of digits, it is a Honaker prime.

It is a nialpdrome in base 12.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (248827) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 124410 + 124411.

It is an arithmetic number, because the mean of its divisors is an integer number (124411).

2²⁴⁸⁸²¹ is an apocalyptic number.

It is an amenable number.

248821 is a deficient number, since it is larger than the sum of its proper divisors (1).

248821 is an equidigital number, since it uses as much as digits as its factorization.

248821 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 1024, while the sum is 25.

The square root of 248821 is about 498.8196066716. The cubic root of 248821 is about 62.8968666162.

The spelling of 248821 in words is "two hundred forty-eight thousand, eight hundred twenty-one".