20648827809 has 27 divisors (see below), whose sum is σ = 31490990739. Its totient is φ = 13036191840.

The previous prime is 20648827781. The next prime is 20648827811. The reversal of 20648827809 is 90872884602.

The square root of 20648827809 is 143697.

It is a perfect power (a square), and thus also a powerful number.

It can be written as a sum of positive squares in only one way, i.e., 16378209 + 20632449600 = 4047^2 + 143640^2 .

It is not a de Polignac number, because 20648827809 - 2⁵ = 20648827777 is a prime.

It is not an unprimeable number, because it can be changed into a prime (20648827879) by changing a digit.

It is a polite number, since it can be written in 26 ways as a sum of consecutive naturals, for example, 8189469 + ... + 8191989.

Almost surely, 2^20648827809 is an apocalyptic number.

20648827809 is the 143697-th square number.

20648827809 is the 71849-th centered octagonal number.

It is an amenable number.

20648827809 is a deficient number, since it is larger than the sum of its proper divisors (10842162930).

20648827809 is an frugal number, since it uses more digits than its factorization.

20648827809 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 5086 (or 2543 counting only the distinct ones).

The product of its (nonzero) digits is 3096576, while the sum is 54.

The spelling of 20648827809 in words is "twenty billion, six hundred forty-eight million, eight hundred twenty-seven thousand, eight hundred nine".