6891487 has 2 divisors, whose sum is σ = 6891488. Its totient is φ = 6891486.

The previous prime is 6891461. The next prime is 6891491. The reversal of 6891487 is 7841986.

It is a strong prime.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-6891487 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (6891427) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 3445743 + 3445744.

It is an arithmetic number, because the mean of its divisors is an integer number (3445744).

Almost surely, 2^6891487 is an apocalyptic number.

6891487 is a deficient number, since it is larger than the sum of its proper divisors (1).

6891487 is an equidigital number, since it uses as much as digits as its factorization.

6891487 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 96768, while the sum is 43.

The square root of 6891487 is about 2625.1641853416. The cubic root of 6891487 is about 190.2994999447.

The spelling of 6891487 in words is "six million, eight hundred ninety-one thousand, four hundred eighty-seven".