21939803 has 8 divisors (see below), whose sum is σ = 22218000. Its totient is φ = 21663648.

The previous prime is 21939791. The next prime is 21939811. The reversal of 21939803 is 30893912.

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

It is a cyclic number.

It is not a de Polignac number, because 21939803 - 2⁶ = 21939739 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (21939823) 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, 33800 + ... + 34442.

It is an arithmetic number, because the mean of its divisors is an integer number (2777250).

Almost surely, 2^21939803 is an apocalyptic number.

21939803 is a deficient number, since it is larger than the sum of its proper divisors (278197).

21939803 is a wasteful number, since it uses less digits than its factorization.

21939803 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1021.

The product of its (nonzero) digits is 11664, while the sum is 35.

The square root of 21939803 is about 4683.9943424389. The cubic root of 21939803 is about 279.9481323994.

The spelling of 21939803 in words is "twenty-one million, nine hundred thirty-nine thousand, eight hundred three".