647040121 has 16 divisors (see below), whose sum is σ = 797779584. Its totient is φ = 511029504.

The previous prime is 647040113. The next prime is 647040161. The reversal of 647040121 is 121040746.

It is a cyclic number.

It is not a de Polignac number, because 647040121 - 2³ = 647040113 is a prime.

It is not an unprimeable number, because it can be changed into a prime (647040161) 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 15 ways as a sum of consecutive naturals, for example, 47361 + ... + 59473.

It is an arithmetic number, because the mean of its divisors is an integer number (49861224).

Almost surely, 2^647040121 is an apocalyptic number.

It is an amenable number.

647040121 is a deficient number, since it is larger than the sum of its proper divisors (150739463).

647040121 is a wasteful number, since it uses less digits than its factorization.

647040121 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 12720.

The product of its (nonzero) digits is 1344, while the sum is 25.

The square root of 647040121 is about 25436.9833313622. The cubic root of 647040121 is about 864.9222516909.

Adding to 647040121 its reverse (121040746), we get a palindrome (768080867).

The spelling of 647040121 in words is "six hundred forty-seven million, forty thousand, one hundred twenty-one".