21533553213 has 16 divisors (see below), whose sum is σ = 29123167680. Its totient is φ = 14150070144.

The previous prime is 21533553191. The next prime is 21533553241. The reversal of 21533553213 is 31235533512.

It is not a de Polignac number, because 21533553213 - 2¹³ = 21533545021 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21533553253) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 324195 + ... + 384927.

It is an arithmetic number, because the mean of its divisors is an integer number (1820197980).

Almost surely, 2^21533553213 is an apocalyptic number.

It is an amenable number.

21533553213 is a deficient number, since it is larger than the sum of its proper divisors (7589614467).

21533553213 is a wasteful number, since it uses less digits than its factorization.

21533553213 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 62428.

The product of its digits is 40500, while the sum is 33.

The spelling of 21533553213 in words is "twenty-one billion, five hundred thirty-three million, five hundred fifty-three thousand, two hundred thirteen".