6421406 has 4 divisors (see below), whose sum is σ = 9632112. Its totient is φ = 3210702.

The previous prime is 6421403. The next prime is 6421417. The reversal of 6421406 is 6041246.

It is a happy number.

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

It is a Curzon number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (6421403) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 1605350 + ... + 1605353.

It is an arithmetic number, because the mean of its divisors is an integer number (2408028).

Almost surely, 2^6421406 is an apocalyptic number.

6421406 is a deficient number, since it is larger than the sum of its proper divisors (3210706).

6421406 is a wasteful number, since it uses less digits than its factorization.

6421406 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 3210705.

The product of its (nonzero) digits is 1152, while the sum is 23.

The square root of 6421406 is about 2534.0493286438. The cubic root of 6421406 is about 185.8703185160.

It can be divided in two parts, 642 and 1406, that added together give a 11-th power (2048 = 2¹¹).

The spelling of 6421406 in words is "six million, four hundred twenty-one thousand, four hundred six".