102020221 has 4 divisors (see below), whose sum is σ = 104190912. Its totient is φ = 99849532.

The previous prime is 102020189. The next prime is 102020227. The reversal of 102020221 is 122020201.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4, and also an emirpimes, since its reverse is a distinct semiprime: 122020201 = 59 ⋅2068139.

It is a cyclic number.

It is not a de Polignac number, because 102020221 - 2⁵ = 102020189 is a prime.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 102020198 and 102020207.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (102020227) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 1085275 + ... + 1085368.

It is an arithmetic number, because the mean of its divisors is an integer number (26047728).

Almost surely, 2^102020221 is an apocalyptic number.

It is an amenable number.

102020221 is a deficient number, since it is larger than the sum of its proper divisors (2170691).

102020221 is an equidigital number, since it uses as much as digits as its factorization.

102020221 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2170690.

The product of its (nonzero) digits is 16, while the sum is 10.

The square root of 102020221 is about 10100.5059774251. The cubic root of 102020221 is about 467.2637463377.

Adding to 102020221 its reverse (122020201), we get a palindrome (224040422).

The spelling of 102020221 in words is "one hundred two million, twenty thousand, two hundred twenty-one".