21587119 has 4 divisors (see below), whose sum is σ = 21601944. Its totient is φ = 21572296.

The previous prime is 21587101. The next prime is 21587131. The reversal of 21587119 is 91178512.

It is a happy number.

It is a semiprime because it is the product of two primes.

It is a cyclic number.

It is not a de Polignac number, because 21587119 - 2¹¹ = 21585071 is a prime.

It is a super-2 number, since 2×21587119² = 932007413440322, which contains 22 as substring.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21587149) 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 3 ways as a sum of consecutive naturals, for example, 4957 + ... + 8230.

It is an arithmetic number, because the mean of its divisors is an integer number (5400486).

Almost surely, 2^21587119 is an apocalyptic number.

21587119 is a deficient number, since it is larger than the sum of its proper divisors (14825).

21587119 is a wasteful number, since it uses less digits than its factorization.

21587119 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 14824.

The product of its digits is 5040, while the sum is 34.

The square root of 21587119 is about 4646.1940338303. The cubic root of 21587119 is about 278.4399594663.

The spelling of 21587119 in words is "twenty-one million, five hundred eighty-seven thousand, one hundred nineteen".