20647308932761 has 27 divisors (see below), whose sum is σ = 24078128660253. Its totient is φ = 17653717206720.

The previous prime is 20647308932753. The next prime is 20647308932791. The reversal of 20647308932761 is 16723980374602.

The square root of 20647308932761 is 4543931.

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 18913757510025 + 1733551422736 = 4348995^2 + 1316644^2 .

It is not a de Polignac number, because 20647308932761 - 2³ = 20647308932753 is a prime.

It is a super-2 number, since 2×20647308932761² (a number of 27 digits) contains 22 as substring.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 20647308932696 and 20647308932705.

It is not an unprimeable number, because it can be changed into a prime (20647308932791) 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 26 ways as a sum of consecutive naturals, for example, 24205520011 + ... + 24205520863.

Almost surely, 2^{20647308932761} is an apocalyptic number.

20647308932761 is the 4543931-st square number.

20647308932761 is the 2271966-th centered octagonal number.

It is an amenable number.

20647308932761 is a deficient number, since it is larger than the sum of its proper divisors (3430819727492).

20647308932761 is an frugal number, since it uses more digits than its factorization.

20647308932761 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 3242 (or 1621 counting only the distinct ones).

The product of its (nonzero) digits is 18289152, while the sum is 58.

The spelling of 20647308932761 in words is "twenty trillion, six hundred forty-seven billion, three hundred eight million, nine hundred thirty-two thousand, seven hundred sixty-one".