21536459 has 8 divisors (see below), whose sum is σ = 24641760. Its totient is φ = 18438336.

The previous prime is 21536453. The next prime is 21536461. The reversal of 21536459 is 95463512.

It is a sphenic number, since it is the product of 3 distinct primes.

It is not a de Polignac number, because 21536459 - 2¹⁶ = 21470923 is a prime.

It is a Duffinian number.

21536459 is a modest number, since divided by 6459 gives 2153 as remainder.

It is not an unprimeable number, because it can be changed into a prime (21536453) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 8927 + ... + 11079.

It is an arithmetic number, because the mean of its divisors is an integer number (3080220).

Almost surely, 2^21536459 is an apocalyptic number.

21536459 is a deficient number, since it is larger than the sum of its proper divisors (3105301).

21536459 is a wasteful number, since it uses less digits than its factorization.

21536459 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 3589.

The product of its digits is 32400, while the sum is 35.

The square root of 21536459 is about 4640.7390575209. The cubic root of 21536459 is about 278.2219773588.

The spelling of 21536459 in words is "twenty-one million, five hundred thirty-six thousand, four hundred fifty-nine".