21603789504 has 224 divisors, whose sum is σ = 69419297280. Its totient is φ = 6533913600.

The previous prime is 21603789497. The next prime is 21603789517. The reversal of 21603789504 is 40598730612.

21603789504 is a `hidden beast` number, since 2 + 1 + 60 + 3 + 7 + 89 + 504 = 666.

It is a self number, because there is not a number n which added to its sum of digits gives 21603789504.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 15642894 + ... + 15644274.

It is a 1-persistent number, because it is pandigital, but 2⋅21603789504 = 43207579008 is not.

Almost surely, 2^21603789504 is an apocalyptic number.

21603789504 is a gapful number since it is divisible by the number (24) formed by its first and last digit.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 21603789504, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (34709648640).

21603789504 is an abundant number, since it is smaller than the sum of its proper divisors (47815507776).

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

21603789504 is a wasteful number, since it uses less digits than its factorization.

21603789504 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 2236 (or 2220 counting only the distinct ones).

The product of its (nonzero) digits is 362880, while the sum is 45.

The spelling of 21603789504 in words is "twenty-one billion, six hundred three million, seven hundred eighty-nine thousand, five hundred four".