646535655 has 32 divisors (see below), whose sum is σ = 1150468800. Its totient is φ = 344497536.

The previous prime is 646535651. The next prime is 646535663. The reversal of 646535655 is 556535646.

646535655 is a `hidden beast` number, since 64 + 6 + 535 + 6 + 55 = 666.

It is not a de Polignac number, because 646535655 - 2² = 646535651 is a prime.

It is a Harshad number since it is a multiple of its sum of digits (45).

It is a self number, because there is not a number n which added to its sum of digits gives 646535655.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (646535651) by changing a digit.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 240177 + ... + 242853.

It is an arithmetic number, because the mean of its divisors is an integer number (35952150).

Almost surely, 2^646535655 is an apocalyptic number.

646535655 is a deficient number, since it is larger than the sum of its proper divisors (503933145).

646535655 is a wasteful number, since it uses less digits than its factorization.

646535655 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 4480 (or 4474 counting only the distinct ones).

The product of its digits is 1620000, while the sum is 45.

The square root of 646535655 is about 25427.0654028340. The cubic root of 646535655 is about 864.6974138500.

Subtracting from 646535655 its reverse (556535646), we obtain a palindrome (90000009).

The spelling of 646535655 in words is "six hundred forty-six million, five hundred thirty-five thousand, six hundred fifty-five".