20512879570642 has 4 divisors (see below), whose sum is σ = 30769319355966. Its totient is φ = 10256439785320.

The previous prime is 20512879570639. The next prime is 20512879570643. The reversal of 20512879570642 is 24607597821502.

It is a semiprime because it is the product of two primes.

It can be written as a sum of positive squares in only one way, i.e., 11342757145801 + 9170122424841 = 3367901^2 + 3028221^2 .

It is a Smith number, since the sum of its digits (58) coincides with the sum of the digits of its prime factors. Since it is squarefree, it is also a hoax number.

It is not an unprimeable number, because it can be changed into a prime (20512879570643) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 5128219892659 + ... + 5128219892662.

Almost surely, 2^{20512879570642} is an apocalyptic number.

20512879570642 is a deficient number, since it is larger than the sum of its proper divisors (10256439785324).

20512879570642 is a wasteful number, since it uses less digits than its factorization.

20512879570642 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 10256439785323.

The product of its (nonzero) digits is 16934400, while the sum is 58.

The spelling of 20512879570642 in words is "twenty trillion, five hundred twelve billion, eight hundred seventy-nine million, five hundred seventy thousand, six hundred forty-two".