9891487 has 2 divisors, whose sum is σ = 9891488. Its totient is φ = 9891486.

The previous prime is 9891473. The next prime is 9891491. The reversal of 9891487 is 7841989.

It is a happy number.

It is a strong prime.

It is an emirp because it is prime and its reverse (7841989) is a distict prime.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-9891487 is a prime.

It is a Chen prime.

It is a plaindrome in base 14.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (9891887) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 4945743 + 4945744.

It is an arithmetic number, because the mean of its divisors is an integer number (4945744).

Almost surely, 2^9891487 is an apocalyptic number.

9891487 is a deficient number, since it is larger than the sum of its proper divisors (1).

9891487 is an equidigital number, since it uses as much as digits as its factorization.

9891487 is an evil number, because the sum of its binary digits is even.

The product of its digits is 145152, while the sum is 46.

The square root of 9891487 is about 3145.0734490628. The cubic root of 9891487 is about 214.6613525790.

The spelling of 9891487 in words is "nine million, eight hundred ninety-one thousand, four hundred eighty-seven".