991434633 has 16 divisors (see below), whose sum is σ = 1512041856. Its totient is φ = 566052480.

The previous prime is 991434601. The next prime is 991434641. The reversal of 991434633 is 336434199.

It is not a de Polignac number, because 991434633 - 2⁵ = 991434601 is a prime.

It is a Curzon number.

It is not an unprimeable number, because it can be changed into a prime (991434673) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 6013 + ... + 44933.

It is an arithmetic number, because the mean of its divisors is an integer number (94502616).

Almost surely, 2^991434633 is an apocalyptic number.

It is an amenable number.

991434633 is a deficient number, since it is larger than the sum of its proper divisors (520607223).

991434633 is a wasteful number, since it uses less digits than its factorization.

991434633 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 40144.

The product of its digits is 209952, while the sum is 42.

The square root of 991434633 is about 31487.0550067802. The cubic root of 991434633 is about 997.1366869299.

The spelling of 991434633 in words is "nine hundred ninety-one million, four hundred thirty-four thousand, six hundred thirty-three".