21520545033 has 32 divisors (see below), whose sum is σ = 32577382656. Its totient is φ = 12536967168.

The previous prime is 21520544993. The next prime is 21520545043. The reversal of 21520545033 is 33054502512.

It is not a de Polignac number, because 21520545033 - 2⁸ = 21520544777 is a prime.

It is not an unprimeable number, because it can be changed into a prime (21520545043) by changing a digit.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 36660 + ... + 210677.

It is an arithmetic number, because the mean of its divisors is an integer number (1018043208).

Almost surely, 2^21520545033 is an apocalyptic number.

21520545033 is a gapful number since it is divisible by the number (23) formed by its first and last digit.

It is an amenable number.

21520545033 is a deficient number, since it is larger than the sum of its proper divisors (11056837623).

21520545033 is a wasteful number, since it uses less digits than its factorization.

21520545033 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 247473.

The product of its (nonzero) digits is 18000, while the sum is 30.

The spelling of 21520545033 in words is "twenty-one billion, five hundred twenty million, five hundred forty-five thousand, thirty-three".