1020201221 has 4 divisors (see below), whose sum is σ = 1098678252. Its totient is φ = 941724192.

The previous prime is 1020201197. The next prime is 1020201253. The reversal of 1020201221 is 1221020201.

It is a happy number.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 1221020201 = 53 ⋅23038117.

It can be written as a sum of positive squares in 2 ways, for example, as 610584100 + 409617121 = 24710^2 + 20239^2 .

It is a cyclic number.

It is not a de Polignac number, because 1020201221 - 2⁶ = 1020201157 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1020201421) 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, 39238496 + ... + 39238521.

It is an arithmetic number, because the mean of its divisors is an integer number (274669563).

Almost surely, 2^1020201221 is an apocalyptic number.

It is an amenable number.

1020201221 is a deficient number, since it is larger than the sum of its proper divisors (78477031).

1020201221 is an equidigital number, since it uses as much as digits as its factorization.

1020201221 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 78477030.

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

The square root of 1020201221 is about 31940.5889269437. The cubic root of 1020201221 is about 1006.6888992039.

Adding to 1020201221 its reverse (1221020201), we get a palindrome (2241221422).

The spelling of 1020201221 in words is "one billion, twenty million, two hundred one thousand, two hundred twenty-one".