9729720 has 384 divisors, whose sum is σ = 44029440. Its totient is φ = 1866240.

The previous prime is 9729697. The next prime is 9729743. The reversal of 9729720 is 279279.

9729720 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is an interprime number because it is at equal distance from previous prime (9729697) and next prime (9729743).

It is a Harshad number since it is a multiple of its sum of digits (36).

It is an Ulam number.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 95 ways as a sum of consecutive naturals, for example, 748434 + ... + 748446.

It is an arithmetic number, because the mean of its divisors is an integer number (114660).

Almost surely, 2^9729720 is an apocalyptic number.

9729720 is a gapful number since it is divisible by the number (90) formed by its first and last digit.

9729720 is the 1560-th decagonal number.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 9729720, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (22014720).

9729720 is an abundant number, since it is smaller than the sum of its proper divisors (34299720).

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

9729720 is a wasteful number, since it uses less digits than its factorization.

9729720 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 57 (or 41 counting only the distinct ones).

The product of its (nonzero) digits is 15876, while the sum is 36.

The square root of 9729720 is about 3119.2499098341. The cubic root of 9729720 is about 213.4847124360.

The spelling of 9729720 in words is "nine million, seven hundred twenty-nine thousand, seven hundred twenty".