9047991 has 4 divisors (see below), whose sum is σ = 12063992. Its totient is φ = 6031992.

The previous prime is 9047963. The next prime is 9047999. The reversal of 9047991 is 1997409.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 1997409 = 3 ⋅665803.

It is not a de Polignac number, because 9047991 - 2⁵ = 9047959 is a prime.

It is a super-2 number, since 2×9047991² = 163732282272162, which contains 22 as substring.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (9047999) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 1507996 + ... + 1508001.

It is an arithmetic number, because the mean of its divisors is an integer number (3015998).

Almost surely, 2^9047991 is an apocalyptic number.

9047991 is a deficient number, since it is larger than the sum of its proper divisors (3016001).

9047991 is a wasteful number, since it uses less digits than its factorization.

9047991 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 3016000.

The product of its (nonzero) digits is 20412, while the sum is 39.

The square root of 9047991 is about 3007.9878656670. The cubic root of 9047991 is about 208.3774504259.

The spelling of 9047991 in words is "nine million, forty-seven thousand, nine hundred ninety-one".