9780640 has 24 divisors (see below), whose sum is σ = 23107140. Its totient is φ = 3912192.

The previous prime is 9780601. The next prime is 9780647. The reversal of 9780640 is 460879.

It can be written as a sum of positive squares in 2 ways, for example, as 8690704 + 1089936 = 2948^2 + 1044^2 .

It is a Smith number, since the sum of its digits (34) coincides with the sum of the digits of its prime factors.

It is a junction number, because it is equal to n+sod(n) for n = 9780596 and 9780605.

It is not an unprimeable number, because it can be changed into a prime (9780647) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 30405 + ... + 30724.

Almost surely, 2^9780640 is an apocalyptic number.

It is an amenable number.

9780640 is an abundant number, since it is smaller than the sum of its proper divisors (13326500).

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

9780640 is a wasteful number, since it uses less digits than its factorization.

9780640 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 61144 (or 61136 counting only the distinct ones).

The product of its (nonzero) digits is 12096, while the sum is 34.

The square root of 9780640 is about 3127.4014772651. The cubic root of 9780640 is about 213.8564851369.

The spelling of 9780640 in words is "nine million, seven hundred eighty thousand, six hundred forty".