646516505 has 8 divisors (see below), whose sum is σ = 782686152. Its totient is φ = 512635648.

The previous prime is 646516489. The next prime is 646516547. The reversal of 646516505 is 505615646.

It can be written as a sum of positive squares in 4 ways, for example, as 58308496 + 588208009 = 7636^2 + 24253^2 .

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 646516505 - 2⁴ = 646516489 is a prime.

It is a Duffinian number.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 571574 + ... + 572703.

It is an arithmetic number, because the mean of its divisors is an integer number (97835769).

Almost surely, 2^646516505 is an apocalyptic number.

It is an amenable number.

646516505 is a deficient number, since it is larger than the sum of its proper divisors (136169647).

646516505 is a wasteful number, since it uses less digits than its factorization.

646516505 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1144395.

The product of its (nonzero) digits is 108000, while the sum is 38.

The square root of 646516505 is about 25426.6888327993. The cubic root of 646516505 is about 864.6888764920.

The spelling of 646516505 in words is "six hundred forty-six million, five hundred sixteen thousand, five hundred five".