20669556831 has 64 divisors (see below), whose sum is σ = 35626106880. Its totient is φ = 10343410560.

The previous prime is 20669556829. The next prime is 20669556839. The reversal of 20669556831 is 13865596602.

It is not a de Polignac number, because 20669556831 - 2¹ = 20669556829 is a prime.

It is a super-2 number, since 2×20669556831² (a number of 21 digits) contains 22 as substring.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (20669556839) by changing a digit.

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 63 ways as a sum of consecutive naturals, for example, 3125130 + ... + 3131736.

It is an arithmetic number, because the mean of its divisors is an integer number (556657920).

Almost surely, 2^20669556831 is an apocalyptic number.

20669556831 is a gapful number since it is divisible by the number (21) formed by its first and last digit.

20669556831 is a deficient number, since it is larger than the sum of its proper divisors (14956550049).

20669556831 is a wasteful number, since it uses less digits than its factorization.

20669556831 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 7124.

The product of its (nonzero) digits is 2332800, while the sum is 51.

The spelling of 20669556831 in words is "twenty billion, six hundred sixty-nine million, five hundred fifty-six thousand, eight hundred thirty-one".