21349008 has 180 divisors, whose sum is σ = 69283760. Its totient is φ = 6345216.

The previous prime is 21349007. The next prime is 21349019. The reversal of 21349008 is 80094312.

It is a Harshad number since it is a multiple of its sum of digits (27).

It is not an unprimeable number, because it can be changed into a prime (21349001) by changing a digit.

It is a polite number, since it can be written in 35 ways as a sum of consecutive naturals, for example, 1123623 + ... + 1123641.

Almost surely, 2^21349008 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 21349008, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (34641880).

21349008 is an abundant number, since it is smaller than the sum of its proper divisors (47934752).

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

21349008 is a wasteful number, since it uses less digits than its factorization.

21349008 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 76 (or 41 counting only the distinct ones).

The product of its (nonzero) digits is 1728, while the sum is 27.

The square root of 21349008 is about 4620.4986743857. The cubic root of 21349008 is about 277.4124194036.

The spelling of 21349008 in words is "twenty-one million, three hundred forty-nine thousand, eight".