21023717533 has 32 divisors (see below), whose sum is σ = 27337282560. Its totient is φ = 15718752000.

The previous prime is 21023717521. The next prime is 21023717557. The reversal of 21023717533 is 33571732012.

It is not a de Polignac number, because 21023717533 - 2⁹ = 21023717021 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21023717503) 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, 39283 + ... + 208783.

It is an arithmetic number, because the mean of its divisors is an integer number (854290080).

Almost surely, 2^21023717533 is an apocalyptic number.

It is an amenable number.

21023717533 is a deficient number, since it is larger than the sum of its proper divisors (6313565027).

21023717533 is a wasteful number, since it uses less digits than its factorization.

21023717533 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 169597.

The product of its (nonzero) digits is 26460, while the sum is 34.

The spelling of 21023717533 in words is "twenty-one billion, twenty-three million, seven hundred seventeen thousand, five hundred thirty-three".