21199968 has 60 divisors (see below), whose sum is σ = 62356140. Its totient is φ = 7065792.

The previous prime is 21199949. The next prime is 21199973. The reversal of 21199968 is 86999112.

It is a nude number because it is divisible by every one of its digits.

It is a congruent number.

It is an unprimeable number.

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 9 ways as a sum of consecutive naturals, for example, 1498 + ... + 6681.

It is an arithmetic number, because the mean of its divisors is an integer number (1039269).

Almost surely, 2^21199968 is an apocalyptic number.

It is an amenable number.

21199968 is an abundant number, since it is smaller than the sum of its proper divisors (41156172).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

21199968 is an equidigital number, since it uses as much as digits as its factorization.

21199968 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 8201 (or 8184 counting only the distinct ones).

The product of its digits is 69984, while the sum is 45.

The square root of 21199968 is about 4604.3422983093. The cubic root of 21199968 is about 276.7653614757.

The spelling of 21199968 in words is "twenty-one million, one hundred ninety-nine thousand, nine hundred sixty-eight".