6421693 has 4 divisors (see below), whose sum is σ = 6444828. Its totient is φ = 6398560.

The previous prime is 6421643. The next prime is 6421697. The reversal of 6421693 is 3961246.

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

It can be written as a sum of positive squares in 2 ways, for example, as 2630884 + 3790809 = 1622^2 + 1947^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-6421693 is a prime.

It is a Smith number, since the sum of its digits (31) coincides with the sum of the digits of its prime factors. Since it is squarefree, it is also a hoax number.

It is a d-powerful number, because it can be written as 6⁴ + 4¹⁰ + 2²¹ + 1 + 6⁸ + 9³ + 3¹³ .

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (6421697) 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, 11146 + ... + 11707.

It is an arithmetic number, because the mean of its divisors is an integer number (1611207).

Almost surely, 2^6421693 is an apocalyptic number.

It is an amenable number.

6421693 is a deficient number, since it is larger than the sum of its proper divisors (23135).

6421693 is a wasteful number, since it uses less digits than its factorization.

6421693 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 23134.

The product of its digits is 7776, while the sum is 31.

The square root of 6421693 is about 2534.1059567429. The cubic root of 6421693 is about 185.8730875869.

The spelling of 6421693 in words is "six million, four hundred twenty-one thousand, six hundred ninety-three".