20884884709 has 4 divisors (see below), whose sum is σ = 22491414316. Its totient is φ = 19278355104.

The previous prime is 20884884677. The next prime is 20884884749. The reversal of 20884884709 is 90748848802.

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

It can be written as a sum of positive squares in 2 ways, for example, as 6044285025 + 14840599684 = 77745^2 + 121822^2 .

It is a cyclic number.

It is not a de Polignac number, because 20884884709 - 2⁵ = 20884884677 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (20884884749) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 803264784 + ... + 803264809.

It is an arithmetic number, because the mean of its divisors is an integer number (5622853579).

Almost surely, 2^20884884709 is an apocalyptic number.

It is an amenable number.

20884884709 is a deficient number, since it is larger than the sum of its proper divisors (1606529607).

20884884709 is a wasteful number, since it uses less digits than its factorization.

20884884709 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1606529606.

The product of its (nonzero) digits is 8257536, while the sum is 58.

The spelling of 20884884709 in words is "twenty billion, eight hundred eighty-four million, eight hundred eighty-four thousand, seven hundred nine".