21408348 has 48 divisors (see below), whose sum is σ = 55264160. Its totient is φ = 6407424.

The previous prime is 21408347. The next prime is 21408349. The reversal of 21408348 is 84380412.

It is an interprime number because it is at equal distance from previous prime (21408347) and next prime (21408349).

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21408341) 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, 3918 + ... + 7626.

Almost surely, 2^21408348 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 21408348, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (27632080).

21408348 is an abundant number, since it is smaller than the sum of its proper divisors (33855812).

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

21408348 is a wasteful number, since it uses less digits than its factorization.

21408348 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 3766 (or 3764 counting only the distinct ones).

The product of its (nonzero) digits is 6144, while the sum is 30.

The square root of 21408348 is about 4626.9156032934. The cubic root of 21408348 is about 277.6692061146.

The spelling of 21408348 in words is "twenty-one million, four hundred eight thousand, three hundred forty-eight".