21368603 has 4 divisors (see below), whose sum is σ = 21470088. Its totient is φ = 21267120.

The previous prime is 21368591. The next prime is 21368617. The reversal of 21368603 is 30686312.

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 21368603 - 2⁶ = 21368539 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (21368003) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 50426 + ... + 50847.

It is an arithmetic number, because the mean of its divisors is an integer number (5367522).

Almost surely, 2^21368603 is an apocalyptic number.

21368603 is a deficient number, since it is larger than the sum of its proper divisors (101485).

21368603 is a wasteful number, since it uses less digits than its factorization.

21368603 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 101484.

The product of its (nonzero) digits is 5184, while the sum is 29.

The square root of 21368603 is about 4622.6186301706. The cubic root of 21368603 is about 277.4972669698.

The spelling of 21368603 in words is "twenty-one million, three hundred sixty-eight thousand, six hundred three".