646128235 has 8 divisors (see below), whose sum is σ = 786926736. Its totient is φ = 509187360.

The previous prime is 646128221. The next prime is 646128239. The reversal of 646128235 is 532821646.

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

It is not a de Polignac number, because 646128235 - 2⁹ = 646127723 is a prime.

It is a super-3 number, since 3×646128235³ (a number of 27 digits) contains 333 as substring.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 646128194 and 646128203.

It is not an unprimeable number, because it can be changed into a prime (646128239) 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, 964036 + ... + 964705.

It is an arithmetic number, because the mean of its divisors is an integer number (98365842).

Almost surely, 2^646128235 is an apocalyptic number.

646128235 is a deficient number, since it is larger than the sum of its proper divisors (140798501).

646128235 is a wasteful number, since it uses less digits than its factorization.

646128235 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1928813.

The product of its digits is 69120, while the sum is 37.

The square root of 646128235 is about 25419.0525983956. The cubic root of 646128235 is about 864.5157435151.

It can be divided in two parts, 646 and 128235, that added together give a square (128881 = 359²).

The spelling of 646128235 in words is "six hundred forty-six million, one hundred twenty-eight thousand, two hundred thirty-five".