21199780224 has 144 divisors (see below), whose sum is σ = 70964695620. Its totient is φ = 6057063936.

The previous prime is 21199780219. The next prime is 21199780279. The reversal of 21199780224 is 42208799112.

It is a tau number, because it is divible by the number of its divisors (144).

It is a self number, because there is not a number n which added to its sum of digits gives 21199780224.

It is a congruent number.

It is an unprimeable number.

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 17 ways as a sum of consecutive naturals, for example, 131334 + ... + 244229.

Almost surely, 2^21199780224 is an apocalyptic number.

21199780224 is a gapful number since it is divisible by the number (24) formed by its first and last digit.

It is an amenable number.

21199780224 is an abundant number, since it is smaller than the sum of its proper divisors (49764915396).

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

21199780224 is a wasteful number, since it uses less digits than its factorization.

21199780224 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 375597 (or 375575 counting only the distinct ones).

The product of its (nonzero) digits is 145152, while the sum is 45.

The spelling of 21199780224 in words is "twenty-one billion, one hundred ninety-nine million, seven hundred eighty thousand, two hundred twenty-four".