20818702317397 has 8 divisors (see below), whose sum is σ = 20823925095000. Its totient is φ = 20813479820544.

The previous prime is 20818702317389. The next prime is 20818702317433. The reversal of 20818702317397 is 79371320781802.

It can be written as a sum of positive squares in 4 ways, for example, as 14467037841 + 20804235279556 = 120279^2 + 4561166^2 .

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 20818702317397 - 2³ = 20818702317389 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (20818702387397) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 296320729 + ... + 296390977.

It is an arithmetic number, because the mean of its divisors is an integer number (2602990636875).

Almost surely, 2^{20818702317397} is an apocalyptic number.

It is an amenable number.

20818702317397 is a deficient number, since it is larger than the sum of its proper divisors (5222777603).

20818702317397 is an equidigital number, since it uses as much as digits as its factorization.

20818702317397 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 140375.

The product of its (nonzero) digits is 7112448, while the sum is 58.

The spelling of 20818702317397 in words is "twenty trillion, eight hundred eighteen billion, seven hundred two million, three hundred seventeen thousand, three hundred ninety-seven".