65768781 has 16 divisors (see below), whose sum is σ = 97695360. Its totient is φ = 39076800.

The previous prime is 65768779. The next prime is 65768789. The reversal of 65768781 is 18786756.

It is not a de Polignac number, because 65768781 - 2¹ = 65768779 is a prime.

It is a super-2 number, since 2×65768781² = 8651065108451922, which contains 22 as substring.

It is a Curzon number.

It is a self number, because there is not a number n which added to its sum of digits gives 65768781.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (65768789) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 27945 + ... + 30206.

It is an arithmetic number, because the mean of its divisors is an integer number (6105960).

Almost surely, 2^65768781 is an apocalyptic number.

It is an amenable number.

65768781 is a deficient number, since it is larger than the sum of its proper divisors (31926579).

65768781 is a wasteful number, since it uses less digits than its factorization.

65768781 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 58196.

The product of its digits is 564480, while the sum is 48.

The square root of 65768781 is about 8109.7953734974. The cubic root of 65768781 is about 403.6515248979.

The spelling of 65768781 in words is "sixty-five million, seven hundred sixty-eight thousand, seven hundred eighty-one".