20021033231 has 4 divisors (see below), whose sum is σ = 20024224032. Its totient is φ = 20017842432.

The previous prime is 20021033213. The next prime is 20021033233. The reversal of 20021033231 is 13233012002.

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

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-20021033231 is a prime.

It is a super-2 number, since 2×20021033231² (a number of 21 digits) contains 22 as substring.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (20021033233) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 1585970 + ... + 1598543.

It is an arithmetic number, because the mean of its divisors is an integer number (5006056008).

Almost surely, 2^20021033231 is an apocalyptic number.

20021033231 is a deficient number, since it is larger than the sum of its proper divisors (3190801).

20021033231 is an equidigital number, since it uses as much as digits as its factorization.

20021033231 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 3190800.

The product of its (nonzero) digits is 216, while the sum is 17.

Adding to 20021033231 its reverse (13233012002), we get a palindrome (33254045233).

The spelling of 20021033231 in words is "twenty billion, twenty-one million, thirty-three thousand, two hundred thirty-one".