21868803 has 12 divisors (see below), whose sum is σ = 34460088. Its totient is φ = 13253760.

The previous prime is 21868793. The next prime is 21868831. The reversal of 21868803 is 30886812.

It is not a de Polignac number, because 21868803 - 2⁴ = 21868787 is a prime.

It is a Smith number, since the sum of its digits (36) coincides with the sum of the digits of its prime factors.

It is not an unprimeable number, because it can be changed into a prime (21868303) 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 11 ways as a sum of consecutive naturals, for example, 110350 + ... + 110547.

It is an arithmetic number, because the mean of its divisors is an integer number (2871674).

Almost surely, 2^21868803 is an apocalyptic number.

21868803 is a deficient number, since it is larger than the sum of its proper divisors (12591285).

21868803 is a wasteful number, since it uses less digits than its factorization.

21868803 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 220914 (or 220911 counting only the distinct ones).

The product of its (nonzero) digits is 18432, while the sum is 36.

The square root of 21868803 is about 4676.4091993751. The cubic root of 21868803 is about 279.6458234437.

Subtracting 21868803 from its reverse (30886812), we obtain a square (9018009 = 3003²).

The spelling of 21868803 in words is "twenty-one million, eight hundred sixty-eight thousand, eight hundred three".