231300821 has 2 divisors, whose sum is σ = 231300822. Its totient is φ = 231300820.

The previous prime is 231300787. The next prime is 231300829. The reversal of 231300821 is 128003132.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 225420196 + 5880625 = 15014^2 + 2425^2 .

It is a cyclic number.

It is not a de Polignac number, because 231300821 - 2¹⁴ = 231284437 is a prime.

It is a Chen prime.

It is a junction number, because it is equal to n+sod(n) for n = 231300793 and 231300802.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (231300829) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 115650410 + 115650411.

It is an arithmetic number, because the mean of its divisors is an integer number (115650411).

Almost surely, 2^231300821 is an apocalyptic number.

It is an amenable number.

231300821 is a deficient number, since it is larger than the sum of its proper divisors (1).

231300821 is an equidigital number, since it uses as much as digits as its factorization.

231300821 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 288, while the sum is 20.

The square root of 231300821 is about 15208.5772181358. The cubic root of 231300821 is about 613.8454740633.

Adding to 231300821 its reverse (128003132), we get a palindrome (359303953).

The spelling of 231300821 in words is "two hundred thirty-one million, three hundred thousand, eight hundred twenty-one".