21450803 has 4 divisors (see below), whose sum is σ = 23400888. Its totient is φ = 19500720.

The previous prime is 21450799. The next prime is 21450809. The reversal of 21450803 is 30805412.

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 21450803 - 2² = 21450799 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (21450809) 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 3 ways as a sum of consecutive naturals, for example, 975026 + ... + 975047.

It is an arithmetic number, because the mean of its divisors is an integer number (5850222).

Almost surely, 2^21450803 is an apocalyptic number.

21450803 is a deficient number, since it is larger than the sum of its proper divisors (1950085).

21450803 is a wasteful number, since it uses less digits than its factorization.

21450803 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1950084.

The product of its (nonzero) digits is 960, while the sum is 23.

The square root of 21450803 is about 4631.5011605310. The cubic root of 21450803 is about 277.8526339710.

The spelling of 21450803 in words is "twenty-one million, four hundred fifty thousand, eight hundred three".