21741408 has 72 divisors (see below), whose sum is σ = 66594528. Its totient is φ = 6688512.

The previous prime is 21741397. The next prime is 21741409. The reversal of 21741408 is 80414712.

21741408 is a `hidden beast` number, since 217 + 41 + 408 = 666.

It is a tau number, because it is divible by the number of its divisors (72).

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21741409) by changing a digit.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 841 + ... + 6647.

It is an arithmetic number, because the mean of its divisors is an integer number (924924).

Almost surely, 2^21741408 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 21741408, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (33297264).

21741408 is an abundant number, since it is smaller than the sum of its proper divisors (44853120).

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

21741408 is a wasteful number, since it uses less digits than its factorization.

21741408 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 5836 (or 5825 counting only the distinct ones).

The product of its (nonzero) digits is 1792, while the sum is 27.

The square root of 21741408 is about 4662.7682764641. The cubic root of 21741408 is about 279.1017472964.

The spelling of 21741408 in words is "twenty-one million, seven hundred forty-one thousand, four hundred eight".