20200231021 has 4 divisors (see below), whose sum is σ = 20201550012. Its totient is φ = 20198912032.

The previous prime is 20200231013. The next prime is 20200231043. The reversal of 20200231021 is 12013200202.

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 14149102500 + 6051128521 = 118950^2 + 77789^2 .

It is a cyclic number.

It is not a de Polignac number, because 20200231021 - 2³ = 20200231013 is a prime.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 20200230992 and 20200231010.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (20200237021) 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, 636250 + ... + 667243.

It is an arithmetic number, because the mean of its divisors is an integer number (5050387503).

Almost surely, 2^20200231021 is an apocalyptic number.

It is an amenable number.

20200231021 is a deficient number, since it is larger than the sum of its proper divisors (1318991).

20200231021 is a wasteful number, since it uses less digits than its factorization.

20200231021 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1318990.

The product of its (nonzero) digits is 48, while the sum is 13.

Adding to 20200231021 its reverse (12013200202), we get a palindrome (32213431223).

The spelling of 20200231021 in words is "twenty billion, two hundred million, two hundred thirty-one thousand, twenty-one".