21202020031 has 8 divisors (see below), whose sum is σ = 21935227680. Its totient is φ = 20468952672.

The previous prime is 21202020013. The next prime is 21202020041. The reversal of 21202020031 is 13002020212.

It is a sphenic number, since it is the product of 3 distinct primes.

It is a cyclic number.

It is not a de Polignac number, because 21202020031 - 2⁷ = 21202019903 is a prime.

It is a super-2 number, since 2×21202020031² (a number of 21 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 = 21202019993 and 21202020020.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21202020041) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 340861 + ... + 398233.

It is an arithmetic number, because the mean of its divisors is an integer number (2741903460).

Almost surely, 2^21202020031 is an apocalyptic number.

21202020031 is a deficient number, since it is larger than the sum of its proper divisors (733207649).

21202020031 is a wasteful number, since it uses less digits than its factorization.

21202020031 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 70145.

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

Adding to 21202020031 its reverse (13002020212), we get a palindrome (34204040243).

The spelling of 21202020031 in words is "twenty-one billion, two hundred two million, twenty thousand, thirty-one".