6421547 has 4 divisors (see below), whose sum is σ = 7005336. Its totient is φ = 5837760.

The previous prime is 6421523. The next prime is 6421559. The reversal of 6421547 is 7451246.

It is a semiprime because it is the product of two primes.

It is a cyclic number.

It is not a de Polignac number, because 6421547 - 2¹⁰ = 6420523 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (6421507) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 291878 + ... + 291899.

It is an arithmetic number, because the mean of its divisors is an integer number (1751334).

Almost surely, 2^6421547 is an apocalyptic number.

6421547 is a deficient number, since it is larger than the sum of its proper divisors (583789).

6421547 is a wasteful number, since it uses less digits than its factorization.

6421547 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 583788.

The product of its digits is 6720, while the sum is 29.

The square root of 6421547 is about 2534.0771495754. The cubic root of 6421547 is about 185.8716789409.

The spelling of 6421547 in words is "six million, four hundred twenty-one thousand, five hundred forty-seven".