65717819 has 4 divisors (see below), whose sum is σ = 65734944. Its totient is φ = 65700696.

The previous prime is 65717807. The next prime is 65717837. The reversal of 65717819 is 91871756.

It is a semiprime because it is the product of two primes.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-65717819 is a prime.

It is a super-2 number, since 2×65717819² = 8637663468233522, which contains 22 as substring.

It is a Duffinian number.

It is a self number, because there is not a number n which added to its sum of digits gives 65717819.

It is not an unprimeable number, because it can be changed into a prime (65717879) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 149 + ... + 11465.

It is an arithmetic number, because the mean of its divisors is an integer number (16433736).

Almost surely, 2^65717819 is an apocalyptic number.

65717819 is a deficient number, since it is larger than the sum of its proper divisors (17125).

65717819 is a wasteful number, since it uses less digits than its factorization.

65717819 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 17124.

The product of its digits is 105840, while the sum is 44.

The square root of 65717819 is about 8106.6527617754. The cubic root of 65717819 is about 403.5472393275.

The spelling of 65717819 in words is "sixty-five million, seven hundred seventeen thousand, eight hundred nineteen".