21086364 has 96 divisors (see below), whose sum is σ = 56448000. Its totient is φ = 6080256.

The previous prime is 21086347. The next prime is 21086381. The reversal of 21086364 is 46368012.

It is an interprime number because it is at equal distance from previous prime (21086347) and next prime (21086381).

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 266877 + ... + 266955.

It is an arithmetic number, because the mean of its divisors is an integer number (588000).

Almost surely, 2^21086364 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 21086364, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (28224000).

21086364 is an abundant number, since it is smaller than the sum of its proper divisors (35361636).

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

21086364 is a wasteful number, since it uses less digits than its factorization.

21086364 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 187 (or 185 counting only the distinct ones).

The product of its (nonzero) digits is 6912, while the sum is 30.

The square root of 21086364 is about 4591.9891114853. The cubic root of 21086364 is about 276.2701094402.

The spelling of 21086364 in words is "twenty-one million, eighty-six thousand, three hundred sixty-four".