20987320140864 has 1701 divisors, whose sum is σ = 80250305786469. Its totient is φ = 5224757852160.

The previous prime is 20987320140763. The next prime is 20987320140881. The reversal of 20987320140864 is 46804102378902.

The square root of 20987320140864 is 4581192.

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

20987320140864 is a `hidden beast` number, since 2 + 0 + 98 + 73 + 20 + 1 + 408 + 64 = 666.

It can be written as a sum of positive squares in only one way, i.e., 18779742273600 + 2207577867264 = 4333560^2 + 1485792^2 .

It is a self number, because there is not a number n which added to its sum of digits gives 20987320140864.

It is an unprimeable number.

It is a polite number, since it can be written in 242 ways as a sum of consecutive naturals, for example, 313243584159 + ... + 313243584225.

Almost surely, 2^{20987320140864} is an apocalyptic number.

20987320140864 is a gapful number since it is divisible by the number (24) formed by its first and last digit.

20987320140864 is the 4581192-nd square number.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 20987320140864

20987320140864 is an abundant number, since it is smaller than the sum of its proper divisors (59262985645605).

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

20987320140864 is a wasteful number, since it uses less digits than its factorization.

20987320140864 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 262 (or 127 counting only the distinct ones).

The product of its (nonzero) digits is 4644864, while the sum is 54.

The spelling of 20987320140864 in words is "twenty trillion, nine hundred eighty-seven billion, three hundred twenty million, one hundred forty thousand, eight hundred sixty-four".