9931720550 has 12 divisors (see below), whose sum is σ = 18473000316. Its totient is φ = 3972688200.

The previous prime is 9931720543. The next prime is 9931720559. The reversal of 9931720550 is 550271399.

It is a junction number, because it is equal to n+sod(n) for n = 9931720498 and 9931720507.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (9931720559) 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 5 ways as a sum of consecutive naturals, for example, 99317156 + ... + 99317255.

It is an arithmetic number, because the mean of its divisors is an integer number (1539416693).

Almost surely, 2^9931720550 is an apocalyptic number.

9931720550 is a deficient number, since it is larger than the sum of its proper divisors (8541279766).

9931720550 is a wasteful number, since it uses less digits than its factorization.

9931720550 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 198634423 (or 198634418 counting only the distinct ones).

The product of its (nonzero) digits is 85050, while the sum is 41.

The square root of 9931720550 is about 99658.0179915294. The cubic root of 9931720550 is about 2149.5200334767.

The spelling of 9931720550 in words is "nine billion, nine hundred thirty-one million, seven hundred twenty thousand, five hundred fifty".