21108401 has 8 divisors (see below), whose sum is σ = 21403200. Its totient is φ = 20815920.

The previous prime is 21108377. The next prime is 21108403. The reversal of 21108401 is 10480112.

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

It is a cyclic number.

It is not a de Polignac number, because 21108401 - 2¹⁴ = 21092017 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 21108401.

It is not an unprimeable number, because it can be changed into a prime (21108403) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 24740 + ... + 25578.

It is an arithmetic number, because the mean of its divisors is an integer number (2675400).

Almost surely, 2^21108401 is an apocalyptic number.

It is an amenable number.

21108401 is a deficient number, since it is larger than the sum of its proper divisors (294799).

21108401 is a wasteful number, since it uses less digits than its factorization.

21108401 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1159.

The product of its (nonzero) digits is 64, while the sum is 17.

The square root of 21108401 is about 4594.3879897109. The cubic root of 21108401 is about 276.3663176620.

Adding to 21108401 its reverse (10480112), we get a palindrome (31588513).

The spelling of 21108401 in words is "twenty-one million, one hundred eight thousand, four hundred one".