102012221 has 2 divisors, whose sum is σ = 102012222. Its totient is φ = 102012220.

The previous prime is 102012217. The next prime is 102012233. The reversal of 102012221 is 122210201.

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., 59892121 + 42120100 = 7739^2 + 6490^2 .

It is a cyclic number.

It is not a de Polignac number, because 102012221 - 2² = 102012217 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (102012271) 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, 51006110 + 51006111.

It is an arithmetic number, because the mean of its divisors is an integer number (51006111).

Almost surely, 2^102012221 is an apocalyptic number.

It is an amenable number.

102012221 is a deficient number, since it is larger than the sum of its proper divisors (1).

102012221 is an equidigital number, since it uses as much as digits as its factorization.

102012221 is an odious number, because the sum of its binary digits is odd.

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

The square root of 102012221 is about 10100.1099498966. The cubic root of 102012221 is about 467.2515323940.

Adding to 102012221 its reverse (122210201), we get a palindrome (224222422).

The spelling of 102012221 in words is "one hundred two million, twelve thousand, two hundred twenty-one".