20501866705 has 8 divisors (see below), whose sum is σ = 24608749032. Its totient is φ = 16397154048.

The previous prime is 20501866687. The next prime is 20501866739. The reversal of 20501866705 is 50766810502.

It can be written as a sum of positive squares in 4 ways, for example, as 3666544704 + 16835322001 = 60552^2 + 129751^2 .

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 20501866705 - 2¹³ = 20501858513 is a prime.

It is a Duffinian number.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 521554 + ... + 559483.

It is an arithmetic number, because the mean of its divisors is an integer number (3076093629).

Almost surely, 2^20501866705 is an apocalyptic number.

It is an amenable number.

20501866705 is a deficient number, since it is larger than the sum of its proper divisors (4106882327).

20501866705 is a wasteful number, since it uses less digits than its factorization.

20501866705 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1084835.

The product of its (nonzero) digits is 100800, while the sum is 40.

The spelling of 20501866705 in words is "twenty billion, five hundred one million, eight hundred sixty-six thousand, seven hundred five".