64855311920 has 40 divisors (see below), whose sum is σ = 172329830304. Its totient is φ = 22236106752.

The previous prime is 64855311919. The next prime is 64855311929. The reversal of 64855311920 is 2911355846.

It is a happy number.

It is a tau number, because it is divible by the number of its divisors (40).

It is a super-2 number, since 2×64855311920² (a number of 22 digits) contains 22 as substring.

It is not an unprimeable number, because it can be changed into a prime (64855311929) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 57905969 + ... + 57907088.

Almost surely, 2^64855311920 is an apocalyptic number.

It is an amenable number.

64855311920 is an abundant number, since it is smaller than the sum of its proper divisors (107474518384).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

64855311920 is a wasteful number, since it uses less digits than its factorization.

64855311920 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 115813077 (or 115813071 counting only the distinct ones).

The product of its (nonzero) digits is 259200, while the sum is 44.

The spelling of 64855311920 in words is "sixty-four billion, eight hundred fifty-five million, three hundred eleven thousand, nine hundred twenty".