21601344 has 28 divisors (see below), whose sum is σ = 57154064. Its totient is φ = 7200384.

The previous prime is 21601343. The next prime is 21601367. The reversal of 21601344 is 44310612.

It is a hoax number, since the sum of its digits (21) coincides with the sum of the digits of its distinct prime factors.

It is a self number, because there is not a number n which added to its sum of digits gives 21601344.

It is not an unprimeable number, because it can be changed into a prime (21601343) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 56062 + ... + 56445.

Almost surely, 2^21601344 is an apocalyptic number.

21601344 is a gapful number since it is divisible by the number (24) formed by its first and last digit.

It is an amenable number.

21601344 is an abundant number, since it is smaller than the sum of its proper divisors (35552720).

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

21601344 is a wasteful number, since it uses less digits than its factorization.

21601344 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 112522 (or 112512 counting only the distinct ones).

The product of its (nonzero) digits is 576, while the sum is 21.

The square root of 21601344 is about 4647.7246045780. The cubic root of 21601344 is about 278.5011060964.

Adding to 21601344 its reverse (44310612), we get a palindrome (65911956).

It can be divided in two parts, 21601 and 344, that added together give a triangular number (21945 = T₂₀₉).

The spelling of 21601344 in words is "twenty-one million, six hundred one thousand, three hundred forty-four".