21233013553 has 4 divisors (see below), whose sum is σ = 21431453040. Its totient is φ = 21034574068.

The previous prime is 21233013521. The next prime is 21233013611. The reversal of 21233013553 is 35531033212.

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 21233013553 - 2⁵ = 21233013521 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (21233010553) 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, 99219583 + ... + 99219796.

It is an arithmetic number, because the mean of its divisors is an integer number (5357863260).

Almost surely, 2^21233013553 is an apocalyptic number.

It is an amenable number.

21233013553 is a deficient number, since it is larger than the sum of its proper divisors (198439487).

21233013553 is a wasteful number, since it uses less digits than its factorization.

21233013553 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 198439486.

The product of its (nonzero) digits is 8100, while the sum is 28.

Adding to 21233013553 its reverse (35531033212), we get a palindrome (56764046765).

The spelling of 21233013553 in words is "twenty-one billion, two hundred thirty-three million, thirteen thousand, five hundred fifty-three".