21589408 has 12 divisors (see below), whose sum is σ = 42504210. Its totient is φ = 10794688.

The previous prime is 21589367. The next prime is 21589409. The reversal of 21589408 is 80498512.

It can be written as a sum of positive squares in only one way, i.e., 20178064 + 1411344 = 4492^2 + 1188^2 .

It is a super-2 number, since 2×21589408² = 932205075580928, which contains 22 as substring.

It is not an unprimeable number, because it can be changed into a prime (21589409) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 337303 + ... + 337366.

Almost surely, 2^21589408 is an apocalyptic number.

It is an amenable number.

21589408 is a deficient number, since it is larger than the sum of its proper divisors (20914802).

21589408 is an equidigital number, since it uses as much as digits as its factorization.

21589408 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 674679 (or 674671 counting only the distinct ones).

The product of its (nonzero) digits is 23040, while the sum is 37.

The square root of 21589408 is about 4646.4403579515. The cubic root of 21589408 is about 278.4498006212.

The spelling of 21589408 in words is "twenty-one million, five hundred eighty-nine thousand, four hundred eight".