16505231231 has 16 divisors (see below), whose sum is σ = 16866450720. Its totient is φ = 16148428800.

The previous prime is 16505231219. The next prime is 16505231287. The reversal of 16505231231 is 13213250561.

It is a cyclic number.

It is not a de Polignac number, because 16505231231 - 2¹⁰ = 16505230207 is a prime.

It is a super-2 number, since 2×16505231231² (a number of 21 digits) contains 22 as substring.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 16505231194 and 16505231203.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (16505231131) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 12627680 + ... + 12628986.

It is an arithmetic number, because the mean of its divisors is an integer number (1054153170).

Almost surely, 2^16505231231 is an apocalyptic number.

16505231231 is a deficient number, since it is larger than the sum of its proper divisors (361219489).

16505231231 is a wasteful number, since it uses less digits than its factorization.

16505231231 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 2794.

The product of its (nonzero) digits is 5400, while the sum is 29.

Adding to 16505231231 its reverse (13213250561), we get a palindrome (29718481792).

The spelling of 16505231231 in words is "sixteen billion, five hundred five million, two hundred thirty-one thousand, two hundred thirty-one".