20651605571 has 16 divisors (see below), whose sum is σ = 22608791040. Its totient is φ = 18796367520.

The previous prime is 20651605553. The next prime is 20651605633. The reversal of 20651605571 is 17550615602.

It is a cyclic number.

It is not a de Polignac number, because 20651605571 - 2¹⁴ = 20651589187 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (20651505571) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 157355 + ... + 257028.

It is an arithmetic number, because the mean of its divisors is an integer number (1413049440).

Almost surely, 2^20651605571 is an apocalyptic number.

20651605571 is a deficient number, since it is larger than the sum of its proper divisors (1957185469).

20651605571 is a wasteful number, since it uses less digits than its factorization.

20651605571 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 414506.

The product of its (nonzero) digits is 63000, while the sum is 38.

The spelling of 20651605571 in words is "twenty billion, six hundred fifty-one million, six hundred five thousand, five hundred seventy-one".