6521749 has 8 divisors (see below), whose sum is σ = 7250432. Its totient is φ = 5825520.

The previous prime is 6521737. The next prime is 6521759. The reversal of 6521749 is 9471256.

It is a sphenic number, since it is the product of 3 distinct primes.

It is not a de Polignac number, because 6521749 - 2⁵ = 6521717 is a prime.

It is a Duffinian number.

6521749 is a lucky number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (6521759) 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 7 ways as a sum of consecutive naturals, for example, 7689 + ... + 8494.

It is an arithmetic number, because the mean of its divisors is an integer number (906304).

Almost surely, 2^6521749 is an apocalyptic number.

It is an amenable number.

6521749 is a deficient number, since it is larger than the sum of its proper divisors (728683).

6521749 is a wasteful number, since it uses less digits than its factorization.

6521749 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 16227.

The product of its digits is 15120, while the sum is 34.

The square root of 6521749 is about 2553.7715246278. The cubic root of 6521749 is about 186.8334758207.

It can be divided in two parts, 652 and 1749, that added together give a 4-th power (2401 = 7⁴).

The spelling of 6521749 in words is "six million, five hundred twenty-one thousand, seven hundred forty-nine".