202102302120221 has 4 divisors (see below), whose sum is σ = 202103831372700. Its totient is φ = 202100772867744.

The previous prime is 202102302120203. The next prime is 202102302120241. The reversal of 202102302120221 is 122021203201202.

It is a semiprime because it is the product of two primes.

It can be written as a sum of positive squares in 2 ways, for example, as 199709495323321 + 2392806796900 = 14131861^2 + 1546870^2 .

It is a cyclic number.

It is not a de Polignac number, because 202102302120221 - 2¹⁸ = 202102301858077 is a prime.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 202102302120193 and 202102302120202.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (202102302120241) 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, 764427986 + ... + 764692323.

It is an arithmetic number, because the mean of its divisors is an integer number (50525957843175).

Almost surely, 2^{202102302120221} is an apocalyptic number.

It is an amenable number.

202102302120221 is a deficient number, since it is larger than the sum of its proper divisors (1529252479).

202102302120221 is a wasteful number, since it uses less digits than its factorization.

202102302120221 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1529252478.

The product of its (nonzero) digits is 384, while the sum is 20.

Adding to 202102302120221 its reverse (122021203201202), we get a palindrome (324123505321423).

The spelling of 202102302120221 in words is "two hundred two trillion, one hundred two billion, three hundred two million, one hundred twenty thousand, two hundred twenty-one".