78857111 has 2 divisors, whose sum is σ = 78857112. Its totient is φ = 78857110.

The previous prime is 78857083. The next prime is 78857123. The reversal of 78857111 is 11175887.

It is a strong prime.

It is a cyclic number.

It is not a de Polignac number, because 78857111 - 2⁶ = 78857047 is a prime.

It is a Sophie Germain prime.

It is a Chen prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (78857171) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 39428555 + 39428556.

It is an arithmetic number, because the mean of its divisors is an integer number (39428556).

Almost surely, 2^78857111 is an apocalyptic number.

78857111 is a deficient number, since it is larger than the sum of its proper divisors (1).

78857111 is an equidigital number, since it uses as much as digits as its factorization.

78857111 is an evil number, because the sum of its binary digits is even.

The product of its digits is 15680, while the sum is 38.

The square root of 78857111 is about 8880.1526450844. The cubic root of 78857111 is about 428.8251887278.

The spelling of 78857111 in words is "seventy-eight million, eight hundred fifty-seven thousand, one hundred eleven".