21984951873 has 8 divisors (see below), whose sum is σ = 29344557088. Its totient is φ = 14640990624.

The previous prime is 21984951841. The next prime is 21984951883. The reversal of 21984951873 is 37815948912.

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

It is not a de Polignac number, because 21984951873 - 2⁵ = 21984951841 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (21984951883) 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 7 ways as a sum of consecutive naturals, for example, 3907711 + ... + 3913332.

It is an arithmetic number, because the mean of its divisors is an integer number (3668069636).

Almost surely, 2^21984951873 is an apocalyptic number.

It is an amenable number.

21984951873 is a deficient number, since it is larger than the sum of its proper divisors (7359605215).

21984951873 is an equidigital number, since it uses as much as digits as its factorization.

21984951873 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 7821983.

The product of its digits is 4354560, while the sum is 57.

The spelling of 21984951873 in words is "twenty-one billion, nine hundred eighty-four million, nine hundred fifty-one thousand, eight hundred seventy-three".