21427104 has 48 divisors (see below), whose sum is σ = 57183840. Its totient is φ = 7023360.

The previous prime is 21427103. The next prime is 21427121. The reversal of 21427104 is 40172412.

It is a happy number.

It is a tau number, because it is divible by the number of its divisors (48).

It is not an unprimeable number, because it can be changed into a prime (21427103) 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, 4027 + ... + 7685.

It is an arithmetic number, because the mean of its divisors is an integer number (1191330).

Almost surely, 2^21427104 is an apocalyptic number.

21427104 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 21427104, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (28591920).

21427104 is an abundant number, since it is smaller than the sum of its proper divisors (35756736).

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

21427104 is a wasteful number, since it uses less digits than its factorization.

21427104 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 3733 (or 3725 counting only the distinct ones).

The product of its (nonzero) digits is 448, while the sum is 21.

The square root of 21427104 is about 4628.9419957481. The cubic root of 21427104 is about 277.7502717416.

Adding to 21427104 its reverse (40172412), we get a palindrome (61599516).

The spelling of 21427104 in words is "twenty-one million, four hundred twenty-seven thousand, one hundred four".