21433431233 has 4 divisors (see below), whose sum is σ = 21587628720. Its totient is φ = 21279233748.

The previous prime is 21433431193. The next prime is 21433431247. The reversal of 21433431233 is 33213433412.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4.

It is a cyclic number.

It is not a de Polignac number, because 21433431233 - 2⁶ = 21433431169 is a prime.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 21433431196 and 21433431205.

It is not an unprimeable number, because it can be changed into a prime (21433331233) 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, 77098535 + ... + 77098812.

It is an arithmetic number, because the mean of its divisors is an integer number (5396907180).

Almost surely, 2^21433431233 is an apocalyptic number.

It is an amenable number.

21433431233 is a deficient number, since it is larger than the sum of its proper divisors (154197487).

21433431233 is a wasteful number, since it uses less digits than its factorization.

21433431233 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 154197486.

The product of its digits is 15552, while the sum is 29.

Adding to 21433431233 its reverse (33213433412), we get a palindrome (54646864645).

The spelling of 21433431233 in words is "twenty-one billion, four hundred thirty-three million, four hundred thirty-one thousand, two hundred thirty-three".