21086496 has 72 divisors (see below), whose sum is σ = 60422544. Its totient is φ = 6975360.

The previous prime is 21086491. The next prime is 21086501. The reversal of 21086496 is 69468012.

21086496 is a `hidden beast` number, since 2 + 1 + 0 + 8 + 649 + 6 = 666.

It is an interprime number because it is at equal distance from previous prime (21086491) and next prime (21086501).

It is a tau number, because it is divible by the number of its divisors (72).

It is a Harshad number since it is a multiple of its sum of digits (36).

It is a self number, because there is not a number n which added to its sum of digits gives 21086496.

It is not an unprimeable number, because it can be changed into a prime (21086491) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (7) of ones.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 60595 + ... + 60941.

It is an arithmetic number, because the mean of its divisors is an integer number (839202).

Almost surely, 2^21086496 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 21086496, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (30211272).

21086496 is an abundant number, since it is smaller than the sum of its proper divisors (39336048).

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

21086496 is a wasteful number, since it uses less digits than its factorization.

21086496 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 574 (or 563 counting only the distinct ones).

The product of its (nonzero) digits is 20736, while the sum is 36.

The square root of 21086496 is about 4592.0034843192. The cubic root of 21086496 is about 276.2706859198.

The spelling of 21086496 in words is "twenty-one million, eighty-six thousand, four hundred ninety-six".