20531202021 has 12 divisors (see below), whose sum is σ = 32352197280. Its totient is φ = 12443152680.

The previous prime is 20531202019. The next prime is 20531202031. The reversal of 20531202021 is 12020213502.

It is not a de Polignac number, because 20531202021 - 2¹ = 20531202019 is a prime.

It is a super-2 number, since 2×20531202021² (a number of 21 digits) contains 22 as substring.

It is a junction number, because it is equal to n+sod(n) for n = 20531201985 and 20531202003.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (20531202031) by changing a digit.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 103692841 + ... + 103693038.

It is an arithmetic number, because the mean of its divisors is an integer number (2696016440).

Almost surely, 2^20531202021 is an apocalyptic number.

It is an amenable number.

20531202021 is a deficient number, since it is larger than the sum of its proper divisors (11820995259).

20531202021 is a wasteful number, since it uses less digits than its factorization.

20531202021 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 207385896 (or 207385893 counting only the distinct ones).

The product of its (nonzero) digits is 240, while the sum is 18.

Adding to 20531202021 its reverse (12020213502), we get a palindrome (32551415523).

The spelling of 20531202021 in words is "twenty billion, five hundred thirty-one million, two hundred two thousand, twenty-one".