6420646 has 8 divisors (see below), whose sum is σ = 9753120. Its totient is φ = 3169608.

The previous prime is 6420599. The next prime is 6420683. The reversal of 6420646 is 6460246.

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

It is an Ulam number.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 20161 + ... + 20476.

It is an arithmetic number, because the mean of its divisors is an integer number (1219140).

Almost surely, 2^6420646 is an apocalyptic number.

6420646 is a deficient number, since it is larger than the sum of its proper divisors (3332474).

6420646 is a wasteful number, since it uses less digits than its factorization.

6420646 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 40718.

The product of its (nonzero) digits is 6912, while the sum is 28.

The square root of 6420646 is about 2533.8993665890. The cubic root of 6420646 is about 185.8629853859.

The spelling of 6420646 in words is "six million, four hundred twenty thousand, six hundred forty-six".