991333361 has 4 divisors (see below), whose sum is σ = 1025517300. Its totient is φ = 957149424.

The previous prime is 991333351. The next prime is 991333367. The reversal of 991333361 is 163333199.

It is a happy number.

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

It can be written as a sum of positive squares in 2 ways, for example, as 468982336 + 522351025 = 21656^2 + 22855^2 .

It is a cyclic number.

It is not a de Polignac number, because 991333361 - 2⁶ = 991333297 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (991333367) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 17091926 + ... + 17091983.

It is an arithmetic number, because the mean of its divisors is an integer number (256379325).

Almost surely, 2^991333361 is an apocalyptic number.

It is an amenable number.

991333361 is a deficient number, since it is larger than the sum of its proper divisors (34183939).

991333361 is a wasteful number, since it uses less digits than its factorization.

991333361 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 34183938.

The product of its digits is 39366, while the sum is 38.

The square root of 991333361 is about 31485.4468127737. The cubic root of 991333361 is about 997.1027342914.

The spelling of 991333361 in words is "nine hundred ninety-one million, three hundred thirty-three thousand, three hundred sixty-one".