65856813 has 8 divisors (see below), whose sum is σ = 95791776. Its totient is φ = 39913200.

The previous prime is 65856809. The next prime is 65856829. The reversal of 65856813 is 31865856.

It is a sphenic number, since it is the product of 3 distinct primes.

It is not a de Polignac number, because 65856813 - 2² = 65856809 is a prime.

It is a Smith number, since the sum of its digits (42) coincides with the sum of the digits of its prime factors. Since it is squarefree, it is also a hoax number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (65856853) 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, 997798 + ... + 997863.

It is an arithmetic number, because the mean of its divisors is an integer number (11973972).

Almost surely, 2^65856813 is an apocalyptic number.

It is an amenable number.

65856813 is a deficient number, since it is larger than the sum of its proper divisors (29934963).

65856813 is a wasteful number, since it uses less digits than its factorization.

65856813 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1995675.

The product of its digits is 172800, while the sum is 42.

The square root of 65856813 is about 8115.2210690775. The cubic root of 65856813 is about 403.8315414549.

The spelling of 65856813 in words is "sixty-five million, eight hundred fifty-six thousand, eight hundred thirteen".