9900640 has 24 divisors (see below), whose sum is σ = 23390640. Its totient is φ = 3960192.

The previous prime is 9900623. The next prime is 9900641. The reversal of 9900640 is 460099.

It is a junction number, because it is equal to n+sod(n) for n = 9900599 and 9900608.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (9900641) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 30780 + ... + 31099.

It is an arithmetic number, because the mean of its divisors is an integer number (974610).

Almost surely, 2^9900640 is an apocalyptic number.

It is an amenable number.

9900640 is an abundant number, since it is smaller than the sum of its proper divisors (13490000).

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

9900640 is a wasteful number, since it uses less digits than its factorization.

9900640 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 61894 (or 61886 counting only the distinct ones).

The product of its (nonzero) digits is 1944, while the sum is 28.

The square root of 9900640 is about 3146.5282455430. The cubic root of 9900640 is about 214.7275438280.

The spelling of 9900640 in words is "nine million, nine hundred thousand, six hundred forty".