6391749 has 24 divisors (see below), whose sum is σ = 10552512. Its totient is φ = 3369600.

The previous prime is 6391729. The next prime is 6391757. The reversal of 6391749 is 9471936.

It is not a de Polignac number, because 6391749 - 2⁵ = 6391717 is a prime.

It is a Harshad number since it is a multiple of its sum of digits (39).

It is a Curzon number.

6391749 is a lucky number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (6391729) 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 in 23 ways as a sum of consecutive naturals, for example, 2649 + ... + 4449.

It is an arithmetic number, because the mean of its divisors is an integer number (439688).

Almost surely, 2^6391749 is an apocalyptic number.

It is an amenable number.

6391749 is a deficient number, since it is larger than the sum of its proper divisors (4160763).

6391749 is a wasteful number, since it uses less digits than its factorization.

6391749 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1837 (or 1824 counting only the distinct ones).

The product of its digits is 40824, while the sum is 39.

The square root of 6391749 is about 2528.1908551373. The cubic root of 6391749 is about 185.5837320543.

It can be divided in two parts, 6391 and 749, that added together give a triangular number (7140 = T₁₁₉).

The spelling of 6391749 in words is "six million, three hundred ninety-one thousand, seven hundred forty-nine".