64640640111 has 4 divisors (see below), whose sum is σ = 86187520152. Its totient is φ = 43093760072.

The previous prime is 64640640101. The next prime is 64640640137. The reversal of 64640640111 is 11104604646.

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 64640640111 - 2⁵ = 64640640079 is a prime.

It is a super-3 number, since 3×64640640111³ (a number of 33 digits) contains 333 as substring.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (64640640101) 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, 10773440016 + ... + 10773440021.

It is an arithmetic number, because the mean of its divisors is an integer number (21546880038).

Almost surely, 2^64640640111 is an apocalyptic number.

64640640111 is a deficient number, since it is larger than the sum of its proper divisors (21546880041).

64640640111 is a wasteful number, since it uses less digits than its factorization.

64640640111 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 21546880040.

The product of its (nonzero) digits is 13824, while the sum is 33.

The spelling of 64640640111 in words is "sixty-four billion, six hundred forty million, six hundred forty thousand, one hundred eleven".