65857645840 has 80 divisors (see below), whose sum is σ = 175719646080. Its totient is φ = 22486026240.

The previous prime is 65857645813. The next prime is 65857645871. The reversal of 65857645840 is 4854675856.

It is a happy number.

It is a tau number, because it is divible by the number of its divisors (80).

It is an unprimeable number.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 109030 + ... + 378949.

It is an arithmetic number, because the mean of its divisors is an integer number (2196495576).

Almost surely, 2^65857645840 is an apocalyptic number.

It is an amenable number.

65857645840 is an abundant number, since it is smaller than the sum of its proper divisors (109862000240).

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

65857645840 is a wasteful number, since it uses less digits than its factorization.

65857645840 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 488240 (or 488234 counting only the distinct ones).

The product of its (nonzero) digits is 32256000, while the sum is 58.

The spelling of 65857645840 in words is "sixty-five billion, eight hundred fifty-seven million, six hundred forty-five thousand, eight hundred forty".