21486593 has 8 divisors (see below), whose sum is σ = 22346280. Its totient is φ = 20634880.

The previous prime is 21486581. The next prime is 21486599. The reversal of 21486593 is 39568412.

It is a happy number.

It can be written as a sum of positive squares in 4 ways, for example, as 8898289 + 12588304 = 2983^2 + 3548^2 .

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

It is a cyclic number.

It is not a de Polignac number, because 21486593 - 2²⁴ = 4709377 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (21486599) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 3833 + ... + 7593.

It is an arithmetic number, because the mean of its divisors is an integer number (2793285).

Almost surely, 2^21486593 is an apocalyptic number.

It is an amenable number.

21486593 is a deficient number, since it is larger than the sum of its proper divisors (859687).

21486593 is a wasteful number, since it uses less digits than its factorization.

21486593 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 3987.

The product of its digits is 51840, while the sum is 38.

The square root of 21486593 is about 4635.3633083071. The cubic root of 21486593 is about 278.0070776108.

The spelling of 21486593 in words is "twenty-one million, four hundred eighty-six thousand, five hundred ninety-three".