20643655041 has 27 divisors (see below), whose sum is σ = 30496477921. Its totient is φ = 13456400424.

The previous prime is 20643655027. The next prime is 20643655049. The reversal of 20643655041 is 14055634602.

The square root of 20643655041 is 143679.

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

20643655041 is a `hidden beast` number, since 2 + 0 + 64 + 3 + 6 + 550 + 41 = 666.

It is not a de Polignac number, because 20643655041 - 2¹⁵ = 20643622273 is a prime.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 20643654987 and 20643655005.

It is not an unprimeable number, because it can be changed into a prime (20643655049) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 26 ways as a sum of consecutive naturals, for example, 20258230 + ... + 20259248.

Almost surely, 2^20643655041 is an apocalyptic number.

20643655041 is the 143679-th square number.

20643655041 is the 71840-th centered octagonal number.

It is an amenable number.

20643655041 is a deficient number, since it is larger than the sum of its proper divisors (9852822880).

20643655041 is an frugal number, since it uses more digits than its factorization.

20643655041 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 2138 (or 1069 counting only the distinct ones).

The product of its (nonzero) digits is 86400, while the sum is 36.

Multiplying 20643655041 by its sum of digits (36), we get a square (743171581476 = 862074²).

It can be divided in two parts, 20643 and 655041, that added together give a square (675684 = 822²).

The spelling of 20643655041 in words is "twenty billion, six hundred forty-three million, six hundred fifty-five thousand, forty-one".