991946 has 4 divisors (see below), whose sum is σ = 1487922. Its totient is φ = 495972.

The previous prime is 991943. The next prime is 991951. The reversal of 991946 is 649199.

991946 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 649199 = 499 ⋅1301.

It can be written as a sum of positive squares in only one way, i.e., 555025 + 436921 = 745^2 + 661^2 .

It is an Ulam number.

It is an inconsummate number, since it does not exist a number n which divided by its sum of digits gives 991946.

It is not an unprimeable number, because it can be changed into a prime (991943) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 247985 + ... + 247988.

2⁹⁹¹⁹⁴⁶ is an apocalyptic number.

991946 is a deficient number, since it is larger than the sum of its proper divisors (495976).

991946 is a wasteful number, since it uses less digits than its factorization.

991946 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 495975.

The product of its digits is 17496, while the sum is 38.

The square root of 991946 is about 995.9648588178. The cubic root of 991946 is about 99.7308093475.

The spelling of 991946 in words is "nine hundred ninety-one thousand, nine hundred forty-six".