640611235 has 8 divisors (see below), whose sum is σ = 838618416. Its totient is φ = 465899040.

The previous prime is 640611233. The next prime is 640611287. The reversal of 640611235 is 532116046.

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

It is not a de Polignac number, because 640611235 - 2¹ = 640611233 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (640611233) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 5823684 + ... + 5823793.

It is an arithmetic number, because the mean of its divisors is an integer number (104827302).

Almost surely, 2^640611235 is an apocalyptic number.

640611235 is a deficient number, since it is larger than the sum of its proper divisors (198007181).

640611235 is a wasteful number, since it uses less digits than its factorization.

640611235 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 11647493.

The product of its (nonzero) digits is 4320, while the sum is 28.

The square root of 640611235 is about 25310.2989907271. The cubic root of 640611235 is about 862.0481357802.

The spelling of 640611235 in words is "six hundred forty million, six hundred eleven thousand, two hundred thirty-five".