21053404433 has 4 divisors (see below), whose sum is σ = 21349931328. Its totient is φ = 20756877540.

The previous prime is 21053404403. The next prime is 21053404481. The reversal of 21053404433 is 33440435012.

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 21053404433 - 2¹² = 21053400337 is a prime.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 21053404396 and 21053404405.

It is not an unprimeable number, because it can be changed into a prime (21053404403) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 148263341 + ... + 148263482.

It is an arithmetic number, because the mean of its divisors is an integer number (5337482832).

Almost surely, 2^21053404433 is an apocalyptic number.

It is an amenable number.

21053404433 is a deficient number, since it is larger than the sum of its proper divisors (296526895).

21053404433 is an equidigital number, since it uses as much as digits as its factorization.

21053404433 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 296526894.

The product of its (nonzero) digits is 17280, while the sum is 29.

Adding to 21053404433 its reverse (33440435012), we get a palindrome (54493839445).

The spelling of 21053404433 in words is "twenty-one billion, fifty-three million, four hundred four thousand, four hundred thirty-three".