21368558 has 8 divisors (see below), whose sum is σ = 33938352. Its totient is φ = 10055776.

The previous prime is 21368539. The next prime is 21368569. The reversal of 21368558 is 85586312.

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

It is a Curzon number.

It is a congruent number.

It is an unprimeable number.

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, 314210 + ... + 314277.

It is an arithmetic number, because the mean of its divisors is an integer number (4242294).

Almost surely, 2^21368558 is an apocalyptic number.

21368558 is a deficient number, since it is larger than the sum of its proper divisors (12569794).

21368558 is a wasteful number, since it uses less digits than its factorization.

21368558 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 628506.

The product of its digits is 57600, while the sum is 38.

The square root of 21368558 is about 4622.6137627970. The cubic root of 21368558 is about 277.4970721765.

The spelling of 21368558 in words is "twenty-one million, three hundred sixty-eight thousand, five hundred fifty-eight".