20688239569 has 8 divisors (see below), whose sum is σ = 21227770368. Its totient is φ = 20150372640.

The previous prime is 20688239521. The next prime is 20688239581. The reversal of 20688239569 is 96593288602.

It is a happy number.

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 20688239569 - 2¹⁵ = 20688206801 is a prime.

It is a super-2 number, since 2×20688239569² (a number of 21 digits) contains 22 as substring.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (20688239599) by changing a digit.

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, 390757 + ... + 440530.

It is an arithmetic number, because the mean of its divisors is an integer number (2653471296).

Almost surely, 2^20688239569 is an apocalyptic number.

It is an amenable number.

20688239569 is a deficient number, since it is larger than the sum of its proper divisors (539530799).

20688239569 is an equidigital number, since it uses as much as digits as its factorization.

20688239569 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 831935.

The product of its (nonzero) digits is 11197440, while the sum is 58.

The spelling of 20688239569 in words is "twenty billion, six hundred eighty-eight million, two hundred thirty-nine thousand, five hundred sixty-nine".