66858107840 has 56 divisors (see below), whose sum is σ = 159356450400. Its totient is φ = 26717948928.

The previous prime is 66858107821. The next prime is 66858107863. The reversal of 66858107840 is 4870185866.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 241886 + ... + 438434.

It is an arithmetic number, because the mean of its divisors is an integer number (2845650900).

Almost surely, 2^66858107840 is an apocalyptic number.

It is an amenable number.

66858107840 is an abundant number, since it is smaller than the sum of its proper divisors (92498342560).

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

66858107840 is a wasteful number, since it uses less digits than its factorization.

66858107840 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 197629 (or 197619 counting only the distinct ones).

The product of its (nonzero) digits is 2580480, while the sum is 53.

The spelling of 66858107840 in words is "sixty-six billion, eight hundred fifty-eight million, one hundred seven thousand, eight hundred forty".