9961618 has 4 divisors (see below), whose sum is σ = 14942430. Its totient is φ = 4980808.

The previous prime is 9961613. The next prime is 9961631. The reversal of 9961618 is 8161699.

It is a semiprime because it is the product of two primes.

It can be written as a sum of positive squares in only one way, i.e., 9102289 + 859329 = 3017^2 + 927^2 .

It is a Smith number, since the sum of its digits (40) coincides with the sum of the digits of its prime factors. Since it is squarefree, it is also a hoax number.

It is not an unprimeable number, because it can be changed into a prime (9961613) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 2490403 + ... + 2490406.

Almost surely, 2^9961618 is an apocalyptic number.

9961618 is a deficient number, since it is larger than the sum of its proper divisors (4980812).

9961618 is a wasteful number, since it uses less digits than its factorization.

9961618 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 4980811.

The product of its digits is 23328, while the sum is 40.

The square root of 9961618 is about 3156.2030986614. The cubic root of 9961618 is about 215.1674772233.

The spelling of 9961618 in words is "nine million, nine hundred sixty-one thousand, six hundred eighteen".