6693991 has 2 divisors, whose sum is σ = 6693992. Its totient is φ = 6693990.

The previous prime is 6693961. The next prime is 6693997. The reversal of 6693991 is 1993966.

It is a strong prime.

It is a cyclic number.

It is not a de Polignac number, because 6693991 - 2¹¹ = 6691943 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (6693997) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 3346995 + 3346996.

It is an arithmetic number, because the mean of its divisors is an integer number (3346996).

Almost surely, 2^6693991 is an apocalyptic number.

6693991 is a deficient number, since it is larger than the sum of its proper divisors (1).

6693991 is an equidigital number, since it uses as much as digits as its factorization.

6693991 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 78732, while the sum is 43.

The square root of 6693991 is about 2587.2748211197. The cubic root of 6693991 is about 188.4639870975.

The spelling of 6693991 in words is "six million, six hundred ninety-three thousand, nine hundred ninety-one".