987491 has 2 divisors, whose sum is σ = 987492. Its totient is φ = 987490.

The previous prime is 987473. The next prime is 987509. The reversal of 987491 is 194789.

987491 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is a balanced prime because it is at equal distance from previous prime (987473) and next prime (987509).

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-987491 is a prime.

It is a Sophie Germain prime.

It is an inconsummate number, since it does not exist a number n which divided by its sum of digits gives 987491.

It is not a weakly prime, because it can be changed into another prime (987191) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 493745 + 493746.

It is an arithmetic number, because the mean of its divisors is an integer number (493746).

2⁹⁸⁷⁴⁹¹ is an apocalyptic number.

987491 is a deficient number, since it is larger than the sum of its proper divisors (1).

987491 is an equidigital number, since it uses as much as digits as its factorization.

987491 is an evil number, because the sum of its binary digits is even.

The product of its digits is 18144, while the sum is 38.

The square root of 987491 is about 993.7258173158. The cubic root of 987491 is about 99.5812825372.

The spelling of 987491 in words is "nine hundred eighty-seven thousand, four hundred ninety-one".