78057911 has 2 divisors, whose sum is σ = 78057912. Its totient is φ = 78057910.

The previous prime is 78057899. The next prime is 78057913. The reversal of 78057911 is 11975087.

It is a strong prime.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-78057911 is a prime.

Together with 78057913, it forms a pair of twin primes.

It is a Chen prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (78057913) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 39028955 + 39028956.

It is an arithmetic number, because the mean of its divisors is an integer number (39028956).

Almost surely, 2^78057911 is an apocalyptic number.

78057911 is a deficient number, since it is larger than the sum of its proper divisors (1).

78057911 is an equidigital number, since it uses as much as digits as its factorization.

78057911 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 17640, while the sum is 38.

The square root of 78057911 is about 8835.0388227783. The cubic root of 78057911 is about 427.3715830102.

The spelling of 78057911 in words is "seventy-eight million, fifty-seven thousand, nine hundred eleven".