21321110001 has 4 divisors (see below), whose sum is σ = 28428146672. Its totient is φ = 14214073332.

The previous prime is 21321109967. The next prime is 21321110003. The reversal of 21321110001 is 10001112312.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4.

It is not a de Polignac number, because 21321110001 - 2¹⁴ = 21321093617 is a prime.

It is a Duffinian number.

It is a Curzon number.

It is not an unprimeable number, because it can be changed into a prime (21321110003) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 3553518331 + ... + 3553518336.

It is an arithmetic number, because the mean of its divisors is an integer number (7107036668).

Almost surely, 2^21321110001 is an apocalyptic number.

It is an amenable number.

21321110001 is a deficient number, since it is larger than the sum of its proper divisors (7107036671).

21321110001 is an equidigital number, since it uses as much as digits as its factorization.

21321110001 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 7107036670.

The product of its (nonzero) digits is 12, while the sum is 12.

Adding to 21321110001 its reverse (10001112312), we get a palindrome (31322222313).

The spelling of 21321110001 in words is "twenty-one billion, three hundred twenty-one million, one hundred ten thousand, one".