20641206247 has 8 divisors (see below), whose sum is σ = 21086721216. Its totient is φ = 20195955552.

The previous prime is 20641206203. The next prime is 20641206259. The reversal of 20641206247 is 74260214602.

It is a sphenic number, since it is the product of 3 distinct primes.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-20641206247 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (20641306247) 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 7 ways as a sum of consecutive naturals, for example, 96073 + ... + 224749.

It is an arithmetic number, because the mean of its divisors is an integer number (2635840152).

Almost surely, 2^20641206247 is an apocalyptic number.

20641206247 is a deficient number, since it is larger than the sum of its proper divisors (445514969).

20641206247 is a wasteful number, since it uses less digits than its factorization.

20641206247 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 132137.

The product of its (nonzero) digits is 32256, while the sum is 34.

The spelling of 20641206247 in words is "twenty billion, six hundred forty-one million, two hundred six thousand, two hundred forty-seven".