21203302231 has 4 divisors (see below), whose sum is σ = 21203656672. Its totient is φ = 21202947792.

The previous prime is 21203302213. The next prime is 21203302247. The reversal of 21203302231 is 13220330212.

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

It is a cyclic number.

It is not a de Polignac number, because 21203302231 - 2⁹ = 21203301719 is a prime.

It is a super-2 number, since 2×21203302231² (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 = 21203302199 and 21203302208.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21203302931) 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, 62910 + ... + 215323.

It is an arithmetic number, because the mean of its divisors is an integer number (5300914168).

Almost surely, 2^21203302231 is an apocalyptic number.

21203302231 is a deficient number, since it is larger than the sum of its proper divisors (354441).

21203302231 is an equidigital number, since it uses as much as digits as its factorization.

21203302231 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 354440.

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

Adding to 21203302231 its reverse (13220330212), we get a palindrome (34423632443).

The spelling of 21203302231 in words is "twenty-one billion, two hundred three million, three hundred two thousand, two hundred thirty-one".