21444401 has 8 divisors (see below), whose sum is σ = 23938464. Its totient is φ = 19041120.

The previous prime is 21444389. The next prime is 21444413. The reversal of 21444401 is 10444412.

It is a happy number.

It is an interprime number because it is at equal distance from previous prime (21444389) and next prime (21444413).

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

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-21444401 is a prime.

It is not an unprimeable number, because it can be changed into a prime (21444431) 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 7 ways as a sum of consecutive naturals, for example, 22196 + ... + 23141.

It is an arithmetic number, because the mean of its divisors is an integer number (2992308).

Almost surely, 2^21444401 is an apocalyptic number.

It is an amenable number.

21444401 is a deficient number, since it is larger than the sum of its proper divisors (2494063).

21444401 is a wasteful number, since it uses less digits than its factorization.

21444401 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 45391.

The product of its (nonzero) digits is 512, while the sum is 20.

The square root of 21444401 is about 4630.8099723483. The cubic root of 21444401 is about 277.8249894805.

Adding to 21444401 its reverse (10444412), we get a palindrome (31888813).

The spelling of 21444401 in words is "twenty-one million, four hundred forty-four thousand, four hundred one".