2131020020221 has 4 divisors (see below), whose sum is σ = 2152119228444. Its totient is φ = 2109920812000.

The previous prime is 2131020020209. The next prime is 2131020020281. The reversal of 2131020020221 is 1220200201312.

It is a happy number.

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 1898845416196 + 232174604025 = 1377986^2 + 481845^2 .

It is a cyclic number.

It is not a de Polignac number, because 2131020020221 - 2³⁷ = 1993581066749 is a prime.

It is a super-2 number, since 2×2131020020221² (a number of 25 digits) contains 22 as substring.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 2131020020195 and 2131020020204.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (2131020020281) 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, 10549603960 + ... + 10549604161.

It is an arithmetic number, because the mean of its divisors is an integer number (538029807111).

Almost surely, 2^{2131020020221} is an apocalyptic number.

It is an amenable number.

2131020020221 is a deficient number, since it is larger than the sum of its proper divisors (21099208223).

2131020020221 is a wasteful number, since it uses less digits than its factorization.

2131020020221 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 21099208222.

The product of its (nonzero) digits is 96, while the sum is 16.

Adding to 2131020020221 its reverse (1220200201312), we get a palindrome (3351220221533).

The spelling of 2131020020221 in words is "two trillion, one hundred thirty-one billion, twenty million, twenty thousand, two hundred twenty-one".