991134477 has 12 divisors (see below), whose sum is σ = 1464933184. Its totient is φ = 645389640.

The previous prime is 991134439. The next prime is 991134491. The reversal of 991134477 is 774431199.

991134477 is a `hidden beast` number, since 99 + 113 + 447 + 7 = 666.

It is a de Polignac number, because none of the positive numbers 2^k-991134477 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (991134407) by changing a digit.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 1280149 + ... + 1280922.

Almost surely, 2^991134477 is an apocalyptic number.

It is an amenable number.

991134477 is a deficient number, since it is larger than the sum of its proper divisors (473798707).

991134477 is a wasteful number, since it uses less digits than its factorization.

991134477 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2561120 (or 2561117 counting only the distinct ones).

The product of its digits is 190512, while the sum is 45.

The square root of 991134477 is about 31482.2883062842. The cubic root of 991134477 is about 997.0360493426.

The spelling of 991134477 in words is "nine hundred ninety-one million, one hundred thirty-four thousand, four hundred seventy-seven".