21408652 has 6 divisors (see below), whose sum is σ = 37465148. Its totient is φ = 10704324.

The previous prime is 21408623. The next prime is 21408659. The reversal of 21408652 is 25680412.

It is a self number, because there is not a number n which added to its sum of digits gives 21408652.

It is not an unprimeable number, because it can be changed into a prime (21408659) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 2676078 + ... + 2676085.

Almost surely, 2^21408652 is an apocalyptic number.

It is an amenable number.

21408652 is a deficient number, since it is larger than the sum of its proper divisors (16056496).

21408652 is a wasteful number, since it uses less digits than its factorization.

21408652 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 5352167 (or 5352165 counting only the distinct ones).

The product of its (nonzero) digits is 3840, while the sum is 28.

The square root of 21408652 is about 4626.9484544352. The cubic root of 21408652 is about 277.6705204156.

The spelling of 21408652 in words is "twenty-one million, four hundred eight thousand, six hundred fifty-two".