78042751 has 2 divisors, whose sum is σ = 78042752. Its totient is φ = 78042750.

The previous prime is 78042737. The next prime is 78042787. The reversal of 78042751 is 15724087.

It is a happy number.

It is a weak prime.

It is an emirp because it is prime and its reverse (15724087) is a distict prime.

It is a cyclic number.

It is not a de Polignac number, because 78042751 - 2⁷ = 78042623 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (78042551) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 39021375 + 39021376.

It is an arithmetic number, because the mean of its divisors is an integer number (39021376).

Almost surely, 2^78042751 is an apocalyptic number.

78042751 is a deficient number, since it is larger than the sum of its proper divisors (1).

78042751 is an equidigital number, since it uses as much as digits as its factorization.

78042751 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 15680, while the sum is 34.

The square root of 78042751 is about 8834.1808335578. The cubic root of 78042751 is about 427.3439139262.

The spelling of 78042751 in words is "seventy-eight million, forty-two thousand, seven hundred fifty-one".