21411001 has 4 divisors (see below), whose sum is σ = 21432100. Its totient is φ = 21389904.

The previous prime is 21410981. The next prime is 21411011. The reversal of 21411001 is 10011412.

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 7728400 + 13682601 = 2780^2 + 3699^2 .

It is a cyclic number.

It is not a de Polignac number, because 21411001 - 2⁵ = 21410969 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (21411011) 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, 8946 + ... + 11083.

It is an arithmetic number, because the mean of its divisors is an integer number (5358025).

Almost surely, 2^21411001 is an apocalyptic number.

It is an amenable number.

21411001 is a deficient number, since it is larger than the sum of its proper divisors (21099).

21411001 is a wasteful number, since it uses less digits than its factorization.

21411001 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 21098.

The product of its (nonzero) digits is 8, while the sum is 10.

The square root of 21411001 is about 4627.2022864794. The cubic root of 21411001 is about 277.6806755653.

Adding to 21411001 its reverse (10011412), we get a palindrome (31422413).

The spelling of 21411001 in words is "twenty-one million, four hundred eleven thousand, one".