31713205478399 has 4 divisors (see below), whose sum is σ = 32250717435720. Its totient is φ = 31175693521080.

The previous prime is 31713205478351. The next prime is 31713205478441. The reversal of 31713205478399 is 99387450231713.

It is a semiprime because it is the product of two primes.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-31713205478399 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 (31713205478309) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 268755978572 + ... + 268755978689.

It is an arithmetic number, because the mean of its divisors is an integer number (8062679358930).

Almost surely, 2^{31713205478399} is an apocalyptic number.

31713205478399 is a deficient number, since it is larger than the sum of its proper divisors (537511957321).

31713205478399 is an equidigital number, since it uses as much as digits as its factorization.

31713205478399 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 537511957320.

The product of its (nonzero) digits is 34292160, while the sum is 62.

The spelling of 31713205478399 in words is "thirty-one trillion, seven hundred thirteen billion, two hundred five million, four hundred seventy-eight thousand, three hundred ninety-nine".