21537030024 has 192 divisors, whose sum is σ = 63653990400. Its totient is φ = 6553353600.

The previous prime is 21537030001. The next prime is 21537030049. The reversal of 21537030024 is 42003073512.

It is a Cunningham number, because it is equal to 146755²-1.

It is a self number, because there is not a number n which added to its sum of digits gives 21537030024.

It is an unprimeable number.

It is a polite number, since it can be written in 47 ways as a sum of consecutive naturals, for example, 11152339 + ... + 11154269.

It is an arithmetic number, because the mean of its divisors is an integer number (331531200).

Almost surely, 2^21537030024 is an apocalyptic number.

21537030024 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 21537030024, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (31826995200).

21537030024 is an abundant number, since it is smaller than the sum of its proper divisors (42116960376).

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

21537030024 is a wasteful number, since it uses less digits than its factorization.

21537030024 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2256 (or 2249 counting only the distinct ones).

The product of its (nonzero) digits is 5040, while the sum is 27.

The spelling of 21537030024 in words is "twenty-one billion, five hundred thirty-seven million, thirty thousand, twenty-four".