646242569 has 8 divisors (see below), whose sum is σ = 770674560. Its totient is φ = 529838496.

The previous prime is 646242559. The next prime is 646242577. The reversal of 646242569 is 965242646.

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 646242569 - 2¹² = 646238473 is a prime.

It is a super-2 number, since 2×646242569² = 835258915975439522, which contains 22 as substring.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (646242529) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 2006804 + ... + 2007125.

It is an arithmetic number, because the mean of its divisors is an integer number (96334320).

Almost surely, 2^646242569 is an apocalyptic number.

It is an amenable number.

646242569 is a deficient number, since it is larger than the sum of its proper divisors (124431991).

646242569 is a wasteful number, since it uses less digits than its factorization.

646242569 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 4013959.

The product of its digits is 622080, while the sum is 44.

The square root of 646242569 is about 25421.3014812381. The cubic root of 646242569 is about 864.5667332454.

The spelling of 646242569 in words is "six hundred forty-six million, two hundred forty-two thousand, five hundred sixty-nine".