640060647 has 4 divisors (see below), whose sum is σ = 853414200. Its totient is φ = 426707096.

The previous prime is 640060639. The next prime is 640060649. The reversal of 640060647 is 746060046.

640060647 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is a semiprime because it is the product of two primes.

It is a cyclic number.

It is not a de Polignac number, because 640060647 - 2³ = 640060639 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (640060649) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 106676772 + ... + 106676777.

It is an arithmetic number, because the mean of its divisors is an integer number (213353550).

Almost surely, 2^640060647 is an apocalyptic number.

640060647 is a deficient number, since it is larger than the sum of its proper divisors (213353553).

640060647 is a wasteful number, since it uses less digits than its factorization.

640060647 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 213353552.

The product of its (nonzero) digits is 24192, while the sum is 33.

The square root of 640060647 is about 25299.4198945351. The cubic root of 640060647 is about 861.8010959864.

The spelling of 640060647 in words is "six hundred forty million, sixty thousand, six hundred forty-seven".