21968478500 has 24 divisors (see below), whose sum is σ = 47979158136. Its totient is φ = 8787391200.

The previous prime is 21968478473. The next prime is 21968478529. The reversal of 21968478500 is 587486912.

It can be written as a sum of positive squares in 4 ways, for example, as 6329475364 + 15639003136 = 79558^2 + 125056^2 .

It is a super-2 number, since 2×21968478500² (a number of 21 digits) contains 22 as substring.

It is a Harshad number since it is a multiple of its sum of digits (50).

It is an unprimeable number.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 21967979 + ... + 21968978.

It is an arithmetic number, because the mean of its divisors is an integer number (1999131589).

Almost surely, 2^21968478500 is an apocalyptic number.

21968478500 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

21968478500 is an abundant number, since it is smaller than the sum of its proper divisors (26010679636).

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

21968478500 is a wasteful number, since it uses less digits than its factorization.

21968478500 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 43936976 (or 43936964 counting only the distinct ones).

The product of its (nonzero) digits is 967680, while the sum is 50.

The spelling of 21968478500 in words is "twenty-one billion, nine hundred sixty-eight million, four hundred seventy-eight thousand, five hundred".