31305345520 has 40 divisors (see below), whose sum is σ = 72799693200. Its totient is φ = 12519598080.

The previous prime is 31305345509. The next prime is 31305345527. The reversal of 31305345520 is 2554350313.

It is a tau number, because it is divible by the number of its divisors (40).

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (31305345527) 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 7 ways as a sum of consecutive naturals, for example, 385431 + ... + 459529.

It is an arithmetic number, because the mean of its divisors is an integer number (1819992330).

Almost surely, 2^31305345520 is an apocalyptic number.

It is an amenable number.

31305345520 is an abundant number, since it is smaller than the sum of its proper divisors (41494347680).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

31305345520 is a wasteful number, since it uses less digits than its factorization.

31305345520 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 79393 (or 79387 counting only the distinct ones).

The product of its (nonzero) digits is 27000, while the sum is 31.

Adding to 31305345520 its reverse (2554350313), we get a palindrome (33859695833).

The spelling of 31305345520 in words is "thirty-one billion, three hundred five million, three hundred forty-five thousand, five hundred twenty".