31715728573 has 4 divisors (see below), whose sum is σ = 31716833148. Its totient is φ = 31714624000.

The previous prime is 31715728559. The next prime is 31715728609. The reversal of 31715728573 is 37582751713.

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

It can be written as a sum of positive squares in 2 ways, for example, as 5399751289 + 26315977284 = 73483^2 + 162222^2 .

It is a cyclic number.

It is not a de Polignac number, because 31715728573 - 2²¹ = 31713631421 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 (31715728523) 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, 508036 + ... + 567037.

It is an arithmetic number, because the mean of its divisors is an integer number (7929208287).

Almost surely, 2^31715728573 is an apocalyptic number.

It is an amenable number.

31715728573 is a deficient number, since it is larger than the sum of its proper divisors (1104575).

31715728573 is a wasteful number, since it uses less digits than its factorization.

31715728573 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1104574.

The product of its digits is 1234800, while the sum is 49.

The spelling of 31715728573 in words is "thirty-one billion, seven hundred fifteen million, seven hundred twenty-eight thousand, five hundred seventy-three".