21906802803 has 16 divisors (see below), whose sum is σ = 30930370560. Its totient is φ = 13744058496.

The previous prime is 21906802793. The next prime is 21906802823. The reversal of 21906802803 is 30820860912.

It is a happy number.

It is not a de Polignac number, because 21906802803 - 2¹⁶ = 21906737267 is a prime.

It is not an unprimeable number, because it can be changed into a prime (21906802823) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 769326 + ... + 797292.

It is an arithmetic number, because the mean of its divisors is an integer number (1933148160).

Almost surely, 2^21906802803 is an apocalyptic number.

21906802803 is a deficient number, since it is larger than the sum of its proper divisors (9023567757).

21906802803 is a wasteful number, since it uses less digits than its factorization.

21906802803 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 43346.

The product of its (nonzero) digits is 41472, while the sum is 39.

The spelling of 21906802803 in words is "twenty-one billion, nine hundred six million, eight hundred two thousand, eight hundred three".