87491 has 2 divisors, whose sum is σ = 87492. Its totient is φ = 87490.

The previous prime is 87481. The next prime is 87509. The reversal of 87491 is 19478.

It is a weak prime.

It is a cyclic number.

It is not a de Polignac number, because 87491 - 2⁶ = 87427 is a prime.

It is an Ulam number.

It is not a weakly prime, because it can be changed into another prime (87421) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 43745 + 43746.

It is an arithmetic number, because the mean of its divisors is an integer number (43746).

2⁸⁷⁴⁹¹ is an apocalyptic number.

87491 is a deficient number, since it is larger than the sum of its proper divisors (1).

87491 is an equidigital number, since it uses as much as digits as its factorization.

87491 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 2016, while the sum is 29.

The square root of 87491 is about 295.7887759872. The cubic root of 87491 is about 44.3936779138.

The spelling of 87491 in words is "eighty-seven thousand, four hundred ninety-one".