21504153600 has 432 divisors, whose sum is σ = 80401885200. Its totient is φ = 5482414080.

The previous prime is 21504153581. The next prime is 21504153611. The reversal of 21504153600 is 635140512.

21504153600 is a `hidden beast` number, since 2 + 1 + 5 + 0 + 4 + 1 + 53 + 600 = 666.

It is a congruent number.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 35 ways as a sum of consecutive naturals, for example, 10597386 + ... + 10599414.

It is an arithmetic number, because the mean of its divisors is an integer number (186115475).

Almost surely, 2^21504153600 is an apocalyptic number.

21504153600 is a gapful number since it is divisible by the number (20) 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 21504153600, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (40200942600).

21504153600 is an abundant number, since it is smaller than the sum of its proper divisors (58897731600).

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

21504153600 is a wasteful number, since it uses less digits than its factorization.

21504153600 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 2090 (or 2062 counting only the distinct ones).

The product of its (nonzero) digits is 3600, while the sum is 27.

The spelling of 21504153600 in words is "twenty-one billion, five hundred four million, one hundred fifty-three thousand, six hundred".