646662505 has 16 divisors (see below), whose sum is σ = 803081664. Its totient is φ = 499487040.

The previous prime is 646662469. The next prime is 646662517. The reversal of 646662505 is 505266646.

It is not a de Polignac number, because 646662505 - 2¹⁹ = 646138217 is a prime.

It is a Duffinian number.

It is an unprimeable number.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 10894 + ... + 37576.

It is an arithmetic number, because the mean of its divisors is an integer number (50192604).

Almost surely, 2^646662505 is an apocalyptic number.

It is an amenable number.

646662505 is a deficient number, since it is larger than the sum of its proper divisors (156419159).

646662505 is a wasteful number, since it uses less digits than its factorization.

646662505 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 26856.

The product of its (nonzero) digits is 259200, while the sum is 40.

The square root of 646662505 is about 25429.5596698016. The cubic root of 646662505 is about 864.7539612311.

The spelling of 646662505 in words is "six hundred forty-six million, six hundred sixty-two thousand, five hundred five".