31893431720329 has 9 divisors (see below), whose sum is σ = 33660494092263. Its totient is φ = 30214728397152.

The previous prime is 31893431720327. The next prime is 31893431720341. The reversal of 31893431720329 is 92302713439813.

The square root of 31893431720329 is 5647427.

It is a perfect power (a square), and thus also a powerful number.

It can be written as a sum of positive squares in only one way, i.e., 5364830025 + 31888066890304 = 73245^2 + 5646952^2 .

It is not a de Polignac number, because 31893431720329 - 2¹ = 31893431720327 is a prime.

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 31893431720329.

It is not an unprimeable number, because it can be changed into a prime (31893431720321) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written in 8 ways as a sum of consecutive naturals, for example, 107152497 + ... + 107449729.

Almost surely, 2^{31893431720329} is an apocalyptic number.

31893431720329 is the 5647427-th square number.

31893431720329 is the 2823714-th centered octagonal number.

It is an amenable number.

31893431720329 is a deficient number, since it is larger than the sum of its proper divisors (1767062371934).

31893431720329 is an frugal number, since it uses more digits than its factorization.

31893431720329 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 594504 (or 297252 counting only the distinct ones).

The product of its (nonzero) digits is 5878656, while the sum is 55.

The spelling of 31893431720329 in words is "thirty-one trillion, eight hundred ninety-three billion, four hundred thirty-one million, seven hundred twenty thousand, three hundred twenty-nine".