646401565 has 8 divisors (see below), whose sum is σ = 816507360. Its totient is φ = 489904272.

The previous prime is 646401563. The next prime is 646401577. The reversal of 646401565 is 565104646.

646401565 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

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

It is a cyclic number.

It is not a de Polignac number, because 646401565 - 2¹ = 646401563 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (646401563) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 3402019 + ... + 3402208.

It is an arithmetic number, because the mean of its divisors is an integer number (102063420).

Almost surely, 2^646401565 is an apocalyptic number.

It is an amenable number.

646401565 is a deficient number, since it is larger than the sum of its proper divisors (170105795).

646401565 is a wasteful number, since it uses less digits than its factorization.

646401565 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 6804251.

The product of its (nonzero) digits is 86400, while the sum is 37.

The square root of 646401565 is about 25424.4285088180. The cubic root of 646401565 is about 864.6376309687.

The spelling of 646401565 in words is "six hundred forty-six million, four hundred one thousand, five hundred sixty-five".