20817348945 has 8 divisors (see below), whose sum is σ = 33307758336. Its totient is φ = 11102586096.

The previous prime is 20817348943. The next prime is 20817348973. The reversal of 20817348945 is 54984371802.

It is a happy number.

It is a sphenic number, since it is the product of 3 distinct primes.

It is not a de Polignac number, because 20817348945 - 2¹ = 20817348943 is a prime.

It is a super-2 number, since 2×20817348945² (a number of 21 digits) contains 22 as substring.

It is a Smith number, since the sum of its digits (51) coincides with the sum of the digits of its prime factors. Since it is squarefree, it is also a hoax number.

It is not an unprimeable number, because it can be changed into a prime (20817348943) 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 7 ways as a sum of consecutive naturals, for example, 693911617 + ... + 693911646.

It is an arithmetic number, because the mean of its divisors is an integer number (4163469792).

Almost surely, 2^20817348945 is an apocalyptic number.

It is an amenable number.

20817348945 is a deficient number, since it is larger than the sum of its proper divisors (12490409391).

20817348945 is a wasteful number, since it uses less digits than its factorization.

20817348945 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1387823271.

The product of its (nonzero) digits is 1935360, while the sum is 51.

The spelling of 20817348945 in words is "twenty billion, eight hundred seventeen million, three hundred forty-eight thousand, nine hundred forty-five".