640832011 has 4 divisors (see below), whose sum is σ = 641037400. Its totient is φ = 640626624.

The previous prime is 640831999. The next prime is 640832041. The reversal of 640832011 is 110238046.

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 640832011 - 2⁷ = 640831883 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (640832041) 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, 97941 + ... + 104278.

It is an arithmetic number, because the mean of its divisors is an integer number (160259350).

Almost surely, 2^640832011 is an apocalyptic number.

640832011 is a deficient number, since it is larger than the sum of its proper divisors (205389).

640832011 is a wasteful number, since it uses less digits than its factorization.

640832011 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 205388.

The product of its (nonzero) digits is 1152, while the sum is 25.

The square root of 640832011 is about 25314.6600016670. The cubic root of 640832011 is about 862.1471545868.

The spelling of 640832011 in words is "six hundred forty million, eight hundred thirty-two thousand, eleven".