646040791 has 4 divisors (see below), whose sum is σ = 704771784. Its totient is φ = 587309800.

The previous prime is 646040771. The next prime is 646040807. The reversal of 646040791 is 197040646.

646040791 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 not a de Polignac number, because 646040791 - 2¹³ = 646032599 is a prime.

It is a Duffinian number.

It is a self number, because there is not a number n which added to its sum of digits gives 646040791.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (646040761) 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, 29365480 + ... + 29365501.

It is an arithmetic number, because the mean of its divisors is an integer number (176192946).

Almost surely, 2^646040791 is an apocalyptic number.

646040791 is a deficient number, since it is larger than the sum of its proper divisors (58730993).

646040791 is a wasteful number, since it uses less digits than its factorization.

646040791 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 58730992.

The product of its (nonzero) digits is 36288, while the sum is 37.

The square root of 646040791 is about 25417.3324918253. The cubic root of 646040791 is about 864.4767419046.

The spelling of 646040791 in words is "six hundred forty-six million, forty thousand, seven hundred ninety-one".