20021332231 has 4 divisors (see below), whose sum is σ = 20092079272. Its totient is φ = 19950585192.

The previous prime is 20021332189. The next prime is 20021332249. The reversal of 20021332231 is 13223312002.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 13223312002 = 2 ⋅6611656001.

It is a cyclic number.

It is not a de Polignac number, because 20021332231 - 2¹¹ = 20021330183 is a prime.

It is a super-2 number, since 2×20021332231² (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 = 20021332199 and 20021332208.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (20021335231) 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, 35373096 + ... + 35373661.

It is an arithmetic number, because the mean of its divisors is an integer number (5023019818).

Almost surely, 2^20021332231 is an apocalyptic number.

20021332231 is a deficient number, since it is larger than the sum of its proper divisors (70747041).

20021332231 is an equidigital number, since it uses as much as digits as its factorization.

20021332231 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 70747040.

The product of its (nonzero) digits is 432, while the sum is 19.

Adding to 20021332231 its reverse (13223312002), we get a palindrome (33244644233).

The spelling of 20021332231 in words is "twenty billion, twenty-one million, three hundred thirty-two thousand, two hundred thirty-one".