21533463504 has 240 divisors, whose sum is σ = 69753999744. Its totient is φ = 6074265600.

The previous prime is 21533463449. The next prime is 21533463517. The reversal of 21533463504 is 40536433512.

21533463504 is a `hidden beast` number, since 2 + 15 + 3 + 3 + 4 + 635 + 0 + 4 = 666.

It is a Harshad number since it is a multiple of its sum of digits (36).

It is a congruent number.

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 47 ways as a sum of consecutive naturals, for example, 41330764 + ... + 41331284.

Almost surely, 2^21533463504 is an apocalyptic number.

21533463504 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 21533463504, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (34876999872).

21533463504 is an abundant number, since it is smaller than the sum of its proper divisors (48220536240).

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

21533463504 is a wasteful number, since it uses less digits than its factorization.

21533463504 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 986 (or 977 counting only the distinct ones).

The product of its (nonzero) digits is 129600, while the sum is 36.

The spelling of 21533463504 in words is "twenty-one billion, five hundred thirty-three million, four hundred sixty-three thousand, five hundred four".