21023424165 has 8 divisors (see below), whose sum is σ = 33637478688. Its totient is φ = 11212492880.

The previous prime is 21023424143. The next prime is 21023424241. The reversal of 21023424165 is 56142432012.

It is a sphenic number, since it is the product of 3 distinct primes.

It is not a de Polignac number, because 21023424165 - 2⁹ = 21023423653 is a prime.

It is a Curzon number.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 700780791 + ... + 700780820.

It is an arithmetic number, because the mean of its divisors is an integer number (4204684836).

Almost surely, 2^21023424165 is an apocalyptic number.

It is an amenable number.

21023424165 is a deficient number, since it is larger than the sum of its proper divisors (12614054523).

21023424165 is a wasteful number, since it uses less digits than its factorization.

21023424165 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1401561619.

The product of its (nonzero) digits is 11520, while the sum is 30.

Adding to 21023424165 its reverse (56142432012), we get a palindrome (77165856177).

The spelling of 21023424165 in words is "twenty-one billion, twenty-three million, four hundred twenty-four thousand, one hundred sixty-five".