20786961169984 has 63 divisors (see below), whose sum is σ = 42046006264563. Its totient is φ = 10196428849152.

The previous prime is 20786961169981. The next prime is 20786961169991. The reversal of 20786961169984 is 48996116968702.

The square root of 20786961169984 is 4559272.

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

It can be written as a sum of positive squares in 4 ways, for example, as 10327687723584 + 10459273446400 = 3213672^2 + 3234080^2 .

It is a super-2 number, since 2×20786961169984² (a number of 27 digits) contains 22 as substring.

It is a Duffinian number.

It is a self number, because there is not a number n which added to its sum of digits gives 20786961169984.

It is not an unprimeable number, because it can be changed into a prime (20786961169981) by changing a digit.

It is a polite number, since it can be written in 8 ways as a sum of consecutive naturals, for example, 1933125952 + ... + 1933136704.

Almost surely, 2^{20786961169984} is an apocalyptic number.

20786961169984 is the 4559272-nd square number.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 20786961169984

20786961169984 is an abundant number, since it is smaller than the sum of its proper divisors (21259045094579).

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

20786961169984 is an frugal number, since it uses more digits than its factorization.

20786961169984 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 21624 (or 10808 counting only the distinct ones).

The product of its (nonzero) digits is 564350976, while the sum is 76.

The spelling of 20786961169984 in words is "twenty trillion, seven hundred eighty-six billion, nine hundred sixty-one million, one hundred sixty-nine thousand, nine hundred eighty-four".