21440104 has 32 divisors (see below), whose sum is σ = 46428480. Its totient is φ = 9091584.

The previous prime is 21440099. The next prime is 21440119. The reversal of 21440104 is 40104412.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 3459 + ... + 7405.

It is an arithmetic number, because the mean of its divisors is an integer number (1450890).

Almost surely, 2^21440104 is an apocalyptic number.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 21440104, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (23214240).

21440104 is an abundant number, since it is smaller than the sum of its proper divisors (24988376).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

21440104 is a wasteful number, since it uses less digits than its factorization.

21440104 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 4057 (or 4053 counting only the distinct ones).

The product of its (nonzero) digits is 128, while the sum is 16.

The square root of 21440104 is about 4630.3459913920. The cubic root of 21440104 is about 277.8064315094.

Adding to 21440104 its reverse (40104412), we get a palindrome (61544516).

The spelling of 21440104 in words is "twenty-one million, four hundred forty thousand, one hundred four".