21336487 has 8 divisors (see below), whose sum is σ = 22503600. Its totient is φ = 20173824.

The previous prime is 21336473. The next prime is 21336503. The reversal of 21336487 is 78463312.

It is a happy number.

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

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-21336487 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21336407) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 14439 + ... + 15847.

It is an arithmetic number, because the mean of its divisors is an integer number (2812950).

Almost surely, 2^21336487 is an apocalyptic number.

21336487 is a deficient number, since it is larger than the sum of its proper divisors (1167113).

21336487 is a wasteful number, since it uses less digits than its factorization.

21336487 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2225.

The product of its digits is 24192, while the sum is 34.

The square root of 21336487 is about 4619.1435353321. The cubic root of 21336487 is about 277.3581755065.

Adding to 21336487 its reverse (78463312), we get a palindrome (99799799).

The spelling of 21336487 in words is "twenty-one million, three hundred thirty-six thousand, four hundred eighty-seven".