102212021 has 2 divisors, whose sum is σ = 102212022. Its totient is φ = 102212020.

The previous prime is 102212009. The next prime is 102212059. The reversal of 102212021 is 120212201.

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., 59505796 + 42706225 = 7714^2 + 6535^2 .

It is a cyclic number.

It is not a de Polignac number, because 102212021 - 2²⁶ = 35103157 is a prime.

It is a Sophie Germain prime.

It is a Chen prime.

It is a Curzon number.

It is a junction number, because it is equal to n+sod(n) for n = 102211993 and 102212011.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (102212821) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 51106010 + 51106011.

It is an arithmetic number, because the mean of its divisors is an integer number (51106011).

Almost surely, 2^102212021 is an apocalyptic number.

It is an amenable number.

102212021 is a deficient number, since it is larger than the sum of its proper divisors (1).

102212021 is an equidigital number, since it uses as much as digits as its factorization.

102212021 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 16, while the sum is 11.

The square root of 102212021 is about 10109.9960929765. The cubic root of 102212021 is about 467.5563846698.

Adding to 102212021 its reverse (120212201), we get a palindrome (222424222).

The spelling of 102212021 in words is "one hundred two million, two hundred twelve thousand, twenty-one".