21450742316536 has 64 divisors (see below), whose sum is σ = 43603879334400. Its totient is φ = 9834093360000.

The previous prime is 21450742316483. The next prime is 21450742316539. The reversal of 21450742316536 is 63561324705412.

It is a self number, because there is not a number n which added to its sum of digits gives 21450742316536.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21450742316539) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 277278261 + ... + 277355611.

It is an arithmetic number, because the mean of its divisors is an integer number (681310614600).

Almost surely, 2^{21450742316536} is an apocalyptic number.

21450742316536 is a gapful number since it is divisible by the number (26) 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 21450742316536, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (21801939667200).

21450742316536 is an abundant number, since it is smaller than the sum of its proper divisors (22153137017864).

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

21450742316536 is a wasteful number, since it uses less digits than its factorization.

21450742316536 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 95180 (or 95176 counting only the distinct ones).

The product of its (nonzero) digits is 3628800, while the sum is 49.

The spelling of 21450742316536 in words is "twenty-one trillion, four hundred fifty billion, seven hundred forty-two million, three hundred sixteen thousand, five hundred thirty-six".