78850991 has 2 divisors, whose sum is σ = 78850992. Its totient is φ = 78850990.

The previous prime is 78850943. The next prime is 78851039. The reversal of 78850991 is 19905887.

It is a happy number.

It is a balanced prime because it is at equal distance from previous prime (78850943) and next prime (78851039).

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-78850991 is a 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 (78850901) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 39425495 + 39425496.

It is an arithmetic number, because the mean of its divisors is an integer number (39425496).

Almost surely, 2^78850991 is an apocalyptic number.

78850991 is a deficient number, since it is larger than the sum of its proper divisors (1).

78850991 is an equidigital number, since it uses as much as digits as its factorization.

78850991 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 181440, while the sum is 47.

The square root of 78850991 is about 8879.8080497272. The cubic root of 78850991 is about 428.8140949151.

The spelling of 78850991 in words is "seventy-eight million, eight hundred fifty thousand, nine hundred ninety-one".