20647123313 has 4 divisors (see below), whose sum is σ = 20661883200. Its totient is φ = 20632363428.

The previous prime is 20647123307. The next prime is 20647123327. The reversal of 20647123313 is 31332174602.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4.

It is a cyclic number.

It is not a de Polignac number, because 20647123313 - 2¹⁰ = 20647122289 is a prime.

It is a super-2 number, since 2×20647123313² (a number of 21 digits) contains 22 as substring.

It is a Duffinian number.

It is a self number, because there is not a number n which added to its sum of digits gives 20647123313.

It is not an unprimeable number, because it can be changed into a prime (20647123333) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 7377845 + ... + 7380642.

It is an arithmetic number, because the mean of its divisors is an integer number (5165470800).

Almost surely, 2^20647123313 is an apocalyptic number.

It is an amenable number.

20647123313 is a deficient number, since it is larger than the sum of its proper divisors (14759887).

20647123313 is a wasteful number, since it uses less digits than its factorization.

20647123313 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 14759886.

The product of its (nonzero) digits is 18144, while the sum is 32.

Adding to 20647123313 its reverse (31332174602), we get a palindrome (51979297915).

The spelling of 20647123313 in words is "twenty billion, six hundred forty-seven million, one hundred twenty-three thousand, three hundred thirteen".