21349386 has 32 divisors (see below), whose sum is σ = 48254400. Its totient is φ = 6994800.

The previous prime is 21349379. The next prime is 21349403. The reversal of 21349386 is 68394312.

It is a self number, because there is not a number n which added to its sum of digits gives 21349386.

It is an unprimeable number.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 165 + ... + 6536.

It is an arithmetic number, because the mean of its divisors is an integer number (1507950).

Almost surely, 2^21349386 is an apocalyptic number.

It is a practical number, because each smaller number is the sum of distinct divisors of 21349386, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (24127200).

21349386 is an abundant number, since it is smaller than the sum of its proper divisors (26905014).

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

21349386 is a wasteful number, since it uses less digits than its factorization.

21349386 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 6771 (or 6765 counting only the distinct ones).

The product of its digits is 31104, while the sum is 36.

The square root of 21349386 is about 4620.5395788804. The cubic root of 21349386 is about 277.4140566581.

The spelling of 21349386 in words is "twenty-one million, three hundred forty-nine thousand, three hundred eighty-six".