21533045253 has 32 divisors (see below), whose sum is σ = 30295130112. Its totient is φ = 13584278400.

The previous prime is 21533045227. The next prime is 21533045293. The reversal of 21533045253 is 35254033512.

It is not a de Polignac number, because 21533045253 - 2¹⁰ = 21533044229 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21533045213) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 8176825 + ... + 8179457.

It is an arithmetic number, because the mean of its divisors is an integer number (946722816).

Almost surely, 2^21533045253 is an apocalyptic number.

It is an amenable number.

21533045253 is a deficient number, since it is larger than the sum of its proper divisors (8762084859).

21533045253 is a wasteful number, since it uses less digits than its factorization.

21533045253 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 4585.

The product of its (nonzero) digits is 54000, while the sum is 33.

Adding to 21533045253 its reverse (35254033512), we get a palindrome (56787078765).

The spelling of 21533045253 in words is "twenty-one billion, five hundred thirty-three million, forty-five thousand, two hundred fifty-three".