9780099 has 32 divisors (see below), whose sum is σ = 15730176. Its totient is φ = 5287680.

The previous prime is 9780091. The next prime is 9780101. The reversal of 9780099 is 9900879.

It is a happy number.

9780099 is digitally balanced in base 2 and base 4, because in such bases it contains all the possibile digits an equal number of times.

It is not a de Polignac number, because 9780099 - 2³ = 9780091 is a prime.

It is a self number, because there is not a number n which added to its sum of digits gives 9780099.

It is not an unprimeable number, because it can be changed into a prime (9780091) by changing a digit.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 31704 + ... + 32010.

It is an arithmetic number, because the mean of its divisors is an integer number (491568).

Almost surely, 2^9780099 is an apocalyptic number.

9780099 is a deficient number, since it is larger than the sum of its proper divisors (5950077).

9780099 is a wasteful number, since it uses less digits than its factorization.

9780099 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 395.

The product of its (nonzero) digits is 40824, while the sum is 42.

The square root of 9780099 is about 3127.3149825369. The cubic root of 9780099 is about 213.8525420244.

It can be divided in two parts, 97800 and 99, that multiplied together give a triangular number (9682200 = T₄₄₀₀).

The spelling of 9780099 in words is "nine million, seven hundred eighty thousand, ninety-nine".