9961840 has 40 divisors (see below), whose sum is σ = 26471520. Its totient is φ = 3415296.

The previous prime is 9961817. The next prime is 9961841. The reversal of 9961840 is 481699.

It is a tau number, because it is divible by the number of its divisors (40).

It is a self number, because there is not a number n which added to its sum of digits gives 9961840.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (9961841) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (7) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 8335 + ... + 9454.

It is an arithmetic number, because the mean of its divisors is an integer number (661788).

Almost surely, 2^9961840 is an apocalyptic number.

It is an amenable number.

9961840 is an abundant number, since it is smaller than the sum of its proper divisors (16509680).

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

9961840 is a wasteful number, since it uses less digits than its factorization.

9961840 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 17809 (or 17803 counting only the distinct ones).

The product of its (nonzero) digits is 15552, while the sum is 37.

The square root of 9961840 is about 3156.2382673049. The cubic root of 9961840 is about 215.1690755856.

It can be divided in two parts, 9961 and 840, that added together give a palindrome (10801).

The spelling of 9961840 in words is "nine million, nine hundred sixty-one thousand, eight hundred forty".