102320021 has 2 divisors, whose sum is σ = 102320022. Its totient is φ = 102320020.

The previous prime is 102320011. The next prime is 102320083. The reversal of 102320021 is 120023201.

It is a happy number.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 92428996 + 9891025 = 9614^2 + 3145^2 .

It is an emirp because it is prime and its reverse (120023201) is a distict prime.

It is a cyclic number.

It is not a de Polignac number, because 102320021 - 2²⁶ = 35211157 is a prime.

It is a junction number, because it is equal to n+sod(n) for n = 102319984 and 102320011.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (102320011) 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, 51160010 + 51160011.

It is an arithmetic number, because the mean of its divisors is an integer number (51160011).

Almost surely, 2^102320021 is an apocalyptic number.

It is an amenable number.

102320021 is a deficient number, since it is larger than the sum of its proper divisors (1).

102320021 is an equidigital number, since it uses as much as digits as its factorization.

102320021 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 24, while the sum is 11.

The square root of 102320021 is about 10115.3359311493. The cubic root of 102320021 is about 467.7210042983.

Adding to 102320021 its reverse (120023201), we get a palindrome (222343222).

The spelling of 102320021 in words is "one hundred two million, three hundred twenty thousand, twenty-one".