20561627066636 has 24 divisors (see below), whose sum is σ = 40104721525680. Its totient is φ = 9166793490432.

The previous prime is 20561627066599. The next prime is 20561627066657. The reversal of 20561627066636 is 63666072616502.

It is an unprimeable number.

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 7 ways as a sum of consecutive naturals, for example, 7957284725 + ... + 7957287308.

It is an arithmetic number, because the mean of its divisors is an integer number (1671030063570).

Almost surely, 2^{20561627066636} is an apocalyptic number.

It is an amenable number.

20561627066636 is a deficient number, since it is larger than the sum of its proper divisors (19543094459044).

20561627066636 is a wasteful number, since it uses less digits than its factorization.

20561627066636 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 15914572073 (or 15914572071 counting only the distinct ones).

The product of its (nonzero) digits is 19595520, while the sum is 56.

The spelling of 20561627066636 in words is "twenty trillion, five hundred sixty-one billion, six hundred twenty-seven million, sixty-six thousand, six hundred thirty-six".