640306511 has 16 divisors (see below), whose sum is σ = 698090400. Its totient is φ = 583776768.

The previous prime is 640306493. The next prime is 640306529. The reversal of 640306511 is 115603046.

640306511 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is an interprime number because it is at equal distance from previous prime (640306493) and next prime (640306529).

It is a cyclic number.

It is not a de Polignac number, because 640306511 - 2²² = 636112207 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (640306561) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 791075 + ... + 791883.

It is an arithmetic number, because the mean of its divisors is an integer number (43630650).

Almost surely, 2^640306511 is an apocalyptic number.

640306511 is a deficient number, since it is larger than the sum of its proper divisors (57783889).

640306511 is a wasteful number, since it uses less digits than its factorization.

640306511 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1498.

The product of its (nonzero) digits is 2160, while the sum is 26.

The square root of 640306511 is about 25304.2785117458. The cubic root of 640306511 is about 861.9114286250.

Adding to 640306511 its reverse (115603046), we get a palindrome (755909557).

The spelling of 640306511 in words is "six hundred forty million, three hundred six thousand, five hundred eleven".