20917615722084 has 81 divisors (see below), whose sum is σ = 56169594720057. Its totient is φ = 6562242891648.

The previous prime is 20917615722037. The next prime is 20917615722137. The reversal of 20917615722084 is 48022751671902.

The square root of 20917615722084 is 4573578.

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

20917615722084 is a `hidden beast` number, since 2 + 0 + 9 + 1 + 7 + 61 + 572 + 2 + 0 + 8 + 4 = 666.

It can be written as a sum of positive squares in only one way, i.e., 16285340960100 + 4632274761984 = 4035510^2 + 2152272^2 .

It is a self number, because there is not a number n which added to its sum of digits gives 20917615722084.

It is an unprimeable number.

It is a polite number, since it can be written in 26 ways as a sum of consecutive naturals, for example, 466482537 + ... + 466527375.

Almost surely, 2^{20917615722084} is an apocalyptic number.

20917615722084 is the 4573578-th square number.

It is an amenable number.

20917615722084 is an abundant number, since it is smaller than the sum of its proper divisors (35251978997973).

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

20917615722084 is an frugal number, since it uses more digits than its factorization.

20917615722084 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 89722 (or 44861 counting only the distinct ones).

The product of its (nonzero) digits is 3386880, while the sum is 54.

The spelling of 20917615722084 in words is "twenty trillion, nine hundred seventeen billion, six hundred fifteen million, seven hundred twenty-two thousand, eighty-four".