21086500736016 has 135 divisors (see below), whose sum is σ = 59462121966429. Its totient is φ = 6975731644416.

The previous prime is 21086500736003. The next prime is 21086500736017. The reversal of 21086500736016 is 61063700568012.

The square root of 21086500736016 is 4592004.

It is a perfect power (a square), and thus also a powerful number.

21086500736016 is a `hidden beast` number, since 2 + 1 + 0 + 8 + 6 + 500 + 73 + 60 + 16 = 666.

It can be written as a sum of positive squares in only one way, i.e., 19611966531600 + 1474534204416 = 4428540^2 + 1214304^2 .

It is not an unprimeable number, because it can be changed into a prime (21086500736017) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written in 26 ways as a sum of consecutive naturals, for example, 7659461296 + ... + 7659464048.

Almost surely, 2^{21086500736016} is an apocalyptic number.

21086500736016 is the 4592004-th square number.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 21086500736016

21086500736016 is an abundant number, since it is smaller than the sum of its proper divisors (38375621230413).

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

21086500736016 is an frugal number, since it uses more digits than its factorization.

21086500736016 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 5798 (or 2897 counting only the distinct ones).

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

The spelling of 21086500736016 in words is "twenty-one trillion, eighty-six billion, five hundred million, seven hundred thirty-six thousand, sixteen".