21443214433 has 6 divisors (see below), whose sum is σ = 22416064034. Its totient is φ = 20510900256.

The previous prime is 21443214409. The next prime is 21443214437. The reversal of 21443214433 is 33441234412.

It can be written as a sum of positive squares in only one way, i.e., 17526582544 + 3916631889 = 132388^2 + 62583^2 .

It is not a de Polignac number, because 21443214433 - 2⁹ = 21443213921 is a prime.

It is a super-2 number, since 2×21443214433² (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 = 21443214395 and 21443214404.

It is not an unprimeable number, because it can be changed into a prime (21443214437) 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, 20267160 + ... + 20268217.

Almost surely, 2^21443214433 is an apocalyptic number.

21443214433 is a gapful number since it is divisible by the number (23) formed by its first and last digit.

It is an amenable number.

21443214433 is a deficient number, since it is larger than the sum of its proper divisors (972849601).

21443214433 is an equidigital number, since it uses as much as digits as its factorization.

21443214433 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 40535423 (or 40535400 counting only the distinct ones).

The product of its digits is 27648, while the sum is 31.

Adding to 21443214433 its reverse (33441234412), we get a palindrome (54884448845).

The spelling of 21443214433 in words is "twenty-one billion, four hundred forty-three million, two hundred fourteen thousand, four hundred thirty-three".