6421428406 has 8 divisors (see below), whose sum is σ = 9651447000. Its totient is φ = 3204279408.

The previous prime is 6421428401. The next prime is 6421428407. The reversal of 6421428406 is 6048241246.

It is a happy number.

It is a sphenic number, since it is the product of 3 distinct primes.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (6421428401) 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, 3216151 + ... + 3218146.

It is an arithmetic number, because the mean of its divisors is an integer number (1206430875).

Almost surely, 2^6421428406 is an apocalyptic number.

6421428406 is a deficient number, since it is larger than the sum of its proper divisors (3230018594).

6421428406 is a wasteful number, since it uses less digits than its factorization.

6421428406 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 6434798.

The product of its (nonzero) digits is 73728, while the sum is 37.

The square root of 6421428406 is about 80133.8156211221. The cubic root of 6421428406 is about 1858.7053469943.

The spelling of 6421428406 in words is "six billion, four hundred twenty-one million, four hundred twenty-eight thousand, four hundred six".