21424032001 has 4 divisors (see below), whose sum is σ = 21445016404. Its totient is φ = 21403047600.

The previous prime is 21424031983. The next prime is 21424032011. The reversal of 21424032001 is 10023042412.

It is a semiprime because it is the product of two primes.

It can be written as a sum of positive squares in 2 ways, for example, as 14865461776 + 6558570225 = 121924^2 + 80985^2 .

It is a cyclic number.

It is not a de Polignac number, because 21424032001 - 2¹³ = 21424023809 is a prime.

It is a Duffinian number.

It is a self number, because there is not a number n which added to its sum of digits gives 21424032001.

It is not an unprimeable number, because it can be changed into a prime (21424032011) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 10490670 + ... + 10492711.

It is an arithmetic number, because the mean of its divisors is an integer number (5361254101).

Almost surely, 2^21424032001 is an apocalyptic number.

It is an amenable number.

21424032001 is a deficient number, since it is larger than the sum of its proper divisors (20984403).

21424032001 is a wasteful number, since it uses less digits than its factorization.

21424032001 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 20984402.

The product of its (nonzero) digits is 384, while the sum is 19.

Adding to 21424032001 its reverse (10023042412), we get a palindrome (31447074413).

The spelling of 21424032001 in words is "twenty-one billion, four hundred twenty-four million, thirty-two thousand, one".