647121 has 8 divisors (see below), whose sum is σ = 908320. Its totient is φ = 408672.

The previous prime is 647117. The next prime is 647131. The reversal of 647121 is 121746.

It is a sphenic number, since it is the product of 3 distinct primes.

It is not a de Polignac number, because 647121 - 2² = 647117 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (647111) by changing a digit.

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, 5620 + ... + 5733.

It is an arithmetic number, because the mean of its divisors is an integer number (113540).

2⁶⁴⁷¹²¹ is an apocalyptic number.

It is an amenable number.

647121 is a deficient number, since it is larger than the sum of its proper divisors (261199).

647121 is a wasteful number, since it uses less digits than its factorization.

647121 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 11375.

The product of its digits is 336, while the sum is 21.

The square root of 647121 is about 804.4383133591. The cubic root of 647121 is about 86.4958288164.

Adding to 647121 its reverse (121746), we get a palindrome (768867).

It can be divided in two parts, 647 and 121, that multiplied together give a palindrome (78287).

The spelling of 647121 in words is "six hundred forty-seven thousand, one hundred twenty-one".