65378681 has 2 divisors, whose sum is σ = 65378682. Its totient is φ = 65378680.

The previous prime is 65378671. The next prime is 65378699. The reversal of 65378681 is 18687356.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 65205625 + 173056 = 8075^2 + 416^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-65378681 is a prime.

It is a super-2 number, since 2×65378681² = 8548743858599522, which contains 22 as substring.

It is a Chen prime.

It is not a weakly prime, because it can be changed into another prime (65378671) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 32689340 + 32689341.

It is an arithmetic number, because the mean of its divisors is an integer number (32689341).

Almost surely, 2^65378681 is an apocalyptic number.

It is an amenable number.

65378681 is a deficient number, since it is larger than the sum of its proper divisors (1).

65378681 is an equidigital number, since it uses as much as digits as its factorization.

65378681 is an evil number, because the sum of its binary digits is even.

The product of its digits is 241920, while the sum is 44.

The square root of 65378681 is about 8085.7084414416. The cubic root of 65378681 is about 402.8518708427.

The spelling of 65378681 in words is "sixty-five million, three hundred seventy-eight thousand, six hundred eighty-one".