20828664662787 has 24 divisors (see below), whose sum is σ = 31070732404608. Its totient is φ = 13431629433600.

The previous prime is 20828664662777. The next prime is 20828664662791. The reversal of 20828664662787 is 78726646682802.

20828664662787 is a `hidden beast` number, since 2 + 0 + 8 + 2 + 8 + 66 + 466 + 27 + 87 = 666.

It is not a de Polignac number, because 20828664662787 - 2⁶ = 20828664662723 is a prime.

It is not an unprimeable number, because it can be changed into a prime (20828664662747) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 16670268 + ... + 17876105.

It is an arithmetic number, because the mean of its divisors is an integer number (1294613850192).

Almost surely, 2^{20828664662787} is an apocalyptic number.

20828664662787 is a deficient number, since it is larger than the sum of its proper divisors (10242067741821).

20828664662787 is a wasteful number, since it uses less digits than its factorization.

20828664662787 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 34548571 (or 34548568 counting only the distinct ones).

The product of its (nonzero) digits is 1040449536, while the sum is 72.

The spelling of 20828664662787 in words is "twenty trillion, eight hundred twenty-eight billion, six hundred sixty-four million, six hundred sixty-two thousand, seven hundred eighty-seven".