6745521 has 4 divisors (see below), whose sum is σ = 8994032. Its totient is φ = 4497012.

The previous prime is 6745517. The next prime is 6745523. The reversal of 6745521 is 1255476.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4.

It is not a de Polignac number, because 6745521 - 2² = 6745517 is a prime.

It is a super-2 number, since 2×6745521² = 91004107122882, which contains 22 as substring.

It is an Ulam number.

It is a D-number.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (6745523) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 1124251 + ... + 1124256.

It is an arithmetic number, because the mean of its divisors is an integer number (2248508).

Almost surely, 2^6745521 is an apocalyptic number.

It is an amenable number.

6745521 is a deficient number, since it is larger than the sum of its proper divisors (2248511).

6745521 is a wasteful number, since it uses less digits than its factorization.

6745521 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2248510.

The product of its digits is 8400, while the sum is 30.

The square root of 6745521 is about 2597.2140843604. The cubic root of 6745521 is about 188.9463468544.

It can be divided in two parts, 67455 and 21, that added together give a palindrome (67476).

The spelling of 6745521 in words is "six million, seven hundred forty-five thousand, five hundred twenty-one".