9961778 has 4 divisors (see below), whose sum is σ = 14942670. Its totient is φ = 4980888.

The previous prime is 9961771. The next prime is 9961817. The reversal of 9961778 is 8771699.

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., 6416089 + 3545689 = 2533^2 + 1883^2 .

It is a Curzon number.

It is not an unprimeable number, because it can be changed into a prime (9961771) 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 as a sum of consecutive naturals, namely, 2490443 + ... + 2490446.

Almost surely, 2^9961778 is an apocalyptic number.

9961778 is a deficient number, since it is larger than the sum of its proper divisors (4980892).

9961778 is a wasteful number, since it uses less digits than its factorization.

9961778 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 4980891.

The product of its digits is 190512, while the sum is 47.

The square root of 9961778 is about 3156.2284454710. The cubic root of 9961778 is about 215.1686291986.

The spelling of 9961778 in words is "nine million, nine hundred sixty-one thousand, seven hundred seventy-eight".