6645437 has 4 divisors (see below), whose sum is σ = 6874620. Its totient is φ = 6416256.

The previous prime is 6645391. The next prime is 6645461. The reversal of 6645437 is 7345466.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 7345466 = 2 ⋅3672733.

It can be written as a sum of positive squares in 2 ways, for example, as 2343961 + 4301476 = 1531^2 + 2074^2 .

It is a cyclic number.

It is not a de Polignac number, because 6645437 - 2¹⁰ = 6644413 is a prime.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 6645397 and 6645406.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (6645467) 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, 114548 + ... + 114605.

It is an arithmetic number, because the mean of its divisors is an integer number (1718655).

Almost surely, 2^6645437 is an apocalyptic number.

It is an amenable number.

6645437 is a deficient number, since it is larger than the sum of its proper divisors (229183).

6645437 is a wasteful number, since it uses less digits than its factorization.

6645437 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 229182.

The product of its digits is 60480, while the sum is 35.

The square root of 6645437 is about 2577.8745120739. The cubic root of 6645437 is about 188.0072145262.

The spelling of 6645437 in words is "six million, six hundred forty-five thousand, four hundred thirty-seven".