9906780 has 72 divisors (see below), whose sum is σ = 30067632. Its totient is φ = 2436096.

The previous prime is 9906779. The next prime is 9906781. The reversal of 9906780 is 876099.

9906780 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 (9906779) and next prime (9906781).

It is a Harshad number since it is a multiple of its sum of digits (39).

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (9906781) by changing a digit.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 9652 + ... + 10628.

It is an arithmetic number, because the mean of its divisors is an integer number (417606).

Almost surely, 2^9906780 is an apocalyptic number.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 9906780, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (15033816).

9906780 is an abundant number, since it is smaller than the sum of its proper divisors (20160852).

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

9906780 is a wasteful number, since it uses less digits than its factorization.

9906780 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1015 (or 1000 counting only the distinct ones).

The product of its (nonzero) digits is 27216, while the sum is 39.

The square root of 9906780 is about 3147.5037728333. The cubic root of 9906780 is about 214.7719232711.

The spelling of 9906780 in words is "nine million, nine hundred six thousand, seven hundred eighty".