20556812016247 has 8 divisors (see below), whose sum is σ = 23100631563744. Its totient is φ = 18150496228128.

The previous prime is 20556812016163. The next prime is 20556812016269. The reversal of 20556812016247 is 74261021865502.

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

It is a cyclic number.

It is not a de Polignac number, because 20556812016247 - 2²³ = 20556803627639 is a prime.

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 20556812016247.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (20556812046247) 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, 34375939528 + ... + 34375940125.

It is an arithmetic number, because the mean of its divisors is an integer number (2887578945468).

Almost surely, 2^{20556812016247} is an apocalyptic number.

20556812016247 is a deficient number, since it is larger than the sum of its proper divisors (2543819547497).

20556812016247 is a wasteful number, since it uses less digits than its factorization.

20556812016247 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 68751879689.

The product of its (nonzero) digits is 1612800, while the sum is 49.

The spelling of 20556812016247 in words is "twenty trillion, five hundred fifty-six billion, eight hundred twelve million, sixteen thousand, two hundred forty-seven".