20947885456996 has 27 divisors (see below), whose sum is σ = 36728052395769. Its totient is φ = 10454193465408.

The previous prime is 20947885456943. The next prime is 20947885456997. The reversal of 20947885456996 is 69965458874902.

The square root of 20947885456996 is 4576886.

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

It can be written as a sum of positive squares in only one way, i.e., 1871396640100 + 19076488816896 = 1367990^2 + 4367664^2 .

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (20947885456997) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (23) of ones.

It is a polite number, since it can be written in 8 ways as a sum of consecutive naturals, for example, 5666183020 + ... + 5666186716.

Almost surely, 2^{20947885456996} is an apocalyptic number.

20947885456996 is the 4576886-th square number.

It is an amenable number.

20947885456996 is a deficient number, since it is larger than the sum of its proper divisors (15780166938773).

20947885456996 is an frugal number, since it uses more digits than its factorization.

20947885456996 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 8636 (or 4318 counting only the distinct ones).

The product of its (nonzero) digits is 9405849600, while the sum is 82.

The spelling of 20947885456996 in words is "twenty trillion, nine hundred forty-seven billion, eight hundred eighty-five million, four hundred fifty-six thousand, nine hundred ninety-six".