21131443233 has 6 divisors (see below), whose sum is σ = 30523195794. Its totient is φ = 14087628816.

The previous prime is 21131443213. The next prime is 21131443247. The reversal of 21131443233 is 33234413112.

It is a happy number.

21131443233 is a `hidden beast` number, since 21 + 1 + 314 + 4 + 323 + 3 = 666.

It can be written as a sum of positive squares in only one way, i.e., 15166661409 + 5964781824 = 123153^2 + 77232^2 .

It is not a de Polignac number, because 21131443233 - 2¹³ = 21131435041 is a prime.

It is a junction number, because it is equal to n+sod(n) for n = 21131443197 and 21131443206.

It is not an unprimeable number, because it can be changed into a prime (21131443213) by changing a digit.

It is a polite number, since it can be written in 5 ways as a sum of consecutive naturals, for example, 1173969060 + ... + 1173969077.

It is an arithmetic number, because the mean of its divisors is an integer number (5087199299).

Almost surely, 2^21131443233 is an apocalyptic number.

It is an amenable number.

21131443233 is a deficient number, since it is larger than the sum of its proper divisors (9391752561).

21131443233 is a wasteful number, since it uses less digits than its factorization.

21131443233 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 2347938143 (or 2347938140 counting only the distinct ones).

The product of its digits is 5184, while the sum is 27.

Adding to 21131443233 its reverse (33234413112), we get a palindrome (54365856345).

The spelling of 21131443233 in words is "twenty-one billion, one hundred thirty-one million, four hundred forty-three thousand, two hundred thirty-three".