647455 has 4 divisors (see below), whose sum is σ = 776952. Its totient is φ = 517960.

The previous prime is 647453. The next prime is 647477. The reversal of 647455 is 554746.

It is a happy number.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 554746 = 2 ⋅277373.

It is not a de Polignac number, because 647455 - 2¹ = 647453 is a prime.

It is a Smith number, since the sum of its digits (31) coincides with the sum of the digits of its prime factors. Since it is squarefree, it is also a hoax number.

It is a Duffinian number.

647455 is a lucky number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (647453) 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 3 ways as a sum of consecutive naturals, for example, 64741 + ... + 64750.

It is an arithmetic number, because the mean of its divisors is an integer number (194238).

2⁶⁴⁷⁴⁵⁵ is an apocalyptic number.

647455 is a deficient number, since it is larger than the sum of its proper divisors (129497).

647455 is a wasteful number, since it uses less digits than its factorization.

647455 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 129496.

The product of its digits is 16800, while the sum is 31.

The square root of 647455 is about 804.6458848462. The cubic root of 647455 is about 86.5107073517.

The spelling of 647455 in words is "six hundred forty-seven thousand, four hundred fifty-five".