21168001 has 4 divisors (see below), whose sum is σ = 21618432. Its totient is φ = 20717572.

The previous prime is 21167989. The next prime is 21168023. The reversal of 21168001 is 10086112.

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 a cyclic number.

It is not a de Polignac number, because 21168001 - 2⁵ = 21167969 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 21168001.

It is not an unprimeable number, because it can be changed into a prime (21168031) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 225145 + ... + 225238.

It is an arithmetic number, because the mean of its divisors is an integer number (5404608).

Almost surely, 2^21168001 is an apocalyptic number.

It is an amenable number.

21168001 is a deficient number, since it is larger than the sum of its proper divisors (450431).

21168001 is an equidigital number, since it uses as much as digits as its factorization.

21168001 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 450430.

The product of its (nonzero) digits is 96, while the sum is 19.

The square root of 21168001 is about 4600.8695917185. The cubic root of 21168001 is about 276.6261818796.

The spelling of 21168001 in words is "twenty-one million, one hundred sixty-eight thousand, one".