9387991 has 2 divisors, whose sum is σ = 9387992. Its totient is φ = 9387990.

The previous prime is 9387977. The next prime is 9387997. The reversal of 9387991 is 1997839.

It is a strong prime.

It is a cyclic number.

It is not a de Polignac number, because 9387991 - 2¹⁵ = 9355223 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (9387997) 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 as a sum of consecutive naturals, namely, 4693995 + 4693996.

It is an arithmetic number, because the mean of its divisors is an integer number (4693996).

Almost surely, 2^9387991 is an apocalyptic number.

9387991 is a deficient number, since it is larger than the sum of its proper divisors (1).

9387991 is an equidigital number, since it uses as much as digits as its factorization.

9387991 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 122472, while the sum is 46.

The square root of 9387991 is about 3063.9828654873. The cubic root of 9387991 is about 210.9555172283.

The spelling of 9387991 in words is "nine million, three hundred eighty-seven thousand, nine hundred ninety-one".