9891457720 has 32 divisors (see below), whose sum is σ = 22259758320. Its totient is φ = 3955875840.

The previous prime is 9891457691. The next prime is 9891457753. The reversal of 9891457720 is 277541989.

9891457720 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is a Smith number, since the sum of its digits (52) coincides with the sum of the digits of its prime factors.

It is a congruent number.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 244024 + ... + 281656.

Almost surely, 2^9891457720 is an apocalyptic number.

It is an amenable number.

9891457720 is an abundant number, since it is smaller than the sum of its proper divisors (12368300600).

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

9891457720 is a wasteful number, since it uses less digits than its factorization.

9891457720 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 44215 (or 44211 counting only the distinct ones).

The product of its (nonzero) digits is 1270080, while the sum is 52.

The square root of 9891457720 is about 99455.8078746536. The cubic root of 9891457720 is about 2146.6114077096.

The spelling of 9891457720 in words is "nine billion, eight hundred ninety-one million, four hundred fifty-seven thousand, seven hundred twenty".