65978911 has 2 divisors, whose sum is σ = 65978912. Its totient is φ = 65978910.

The previous prime is 65978909. The next prime is 65978917. The reversal of 65978911 is 11987956.

It is a happy number.

It is a weak prime.

It is a cyclic number.

It is not a de Polignac number, because 65978911 - 2¹ = 65978909 is a prime.

It is a super-3 number, since 3×65978911³ (a number of 24 digits) contains 333 as substring.

Together with 65978909, it forms a pair of twin primes.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (65978917) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 32989455 + 32989456.

It is an arithmetic number, because the mean of its divisors is an integer number (32989456).

Almost surely, 2^65978911 is an apocalyptic number.

65978911 is a deficient number, since it is larger than the sum of its proper divisors (1).

65978911 is an equidigital number, since it uses as much as digits as its factorization.

65978911 is an evil number, because the sum of its binary digits is even.

The product of its digits is 136080, while the sum is 46.

The square root of 65978911 is about 8122.7403627101. The cubic root of 65978911 is about 404.0809541886.

The spelling of 65978911 in words is "sixty-five million, nine hundred seventy-eight thousand, nine hundred eleven".