64660128040 has 32 divisors (see below), whose sum is σ = 145493280360. Its totient is φ = 25862630400.

The previous prime is 64660127981. The next prime is 64660128041. The reversal of 64660128040 is 4082106646.

It can be written as a sum of positive squares in 4 ways, for example, as 55021208356 + 9638919684 = 234566^2 + 98178^2 .

It is not an unprimeable number, because it can be changed into a prime (64660128041) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 990820 + ... + 1054060.

Almost surely, 2^64660128040 is an apocalyptic number.

It is an amenable number.

64660128040 is an abundant number, since it is smaller than the sum of its proper divisors (80833152320).

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

64660128040 is a wasteful number, since it uses less digits than its factorization.

64660128040 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 88813 (or 88809 counting only the distinct ones).

The product of its (nonzero) digits is 55296, while the sum is 37.

The spelling of 64660128040 in words is "sixty-four billion, six hundred sixty million, one hundred twenty-eight thousand, forty".