21727104 has 128 divisors (see below), whose sum is σ = 67564800. Its totient is φ = 6057984.

The previous prime is 21727093. The next prime is 21727109. The reversal of 21727104 is 40172712.

It is a tau number, because it is divible by the number of its divisors (128).

It is a Harshad number since it is a multiple of its sum of digits (24).

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21727109) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 158524 + ... + 158660.

It is an arithmetic number, because the mean of its divisors is an integer number (527850).

Almost surely, 2^21727104 is an apocalyptic number.

21727104 is a gapful number since it is divisible by the number (24) formed by its first and last digit.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 21727104, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (33782400).

21727104 is an abundant number, since it is smaller than the sum of its proper divisors (45837696).

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

21727104 is a wasteful number, since it uses less digits than its factorization.

21727104 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 220 (or 208 counting only the distinct ones).

The product of its (nonzero) digits is 784, while the sum is 24.

The square root of 21727104 is about 4661.2341713327. The cubic root of 21727104 is about 279.0405254528.

Adding to 21727104 its reverse (40172712), we get a palindrome (61899816).

The spelling of 21727104 in words is "twenty-one million, seven hundred twenty-seven thousand, one hundred four".