78708251 has 2 divisors, whose sum is σ = 78708252. Its totient is φ = 78708250.

The previous prime is 78708209. The next prime is 78708263. The reversal of 78708251 is 15280787.

It is a strong prime.

It is an emirp because it is prime and its reverse (15280787) is a distict prime.

It is a cyclic number.

It is not a de Polignac number, because 78708251 - 2⁶ = 78708187 is a prime.

It is not a weakly prime, because it can be changed into another prime (78708271) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 39354125 + 39354126.

It is an arithmetic number, because the mean of its divisors is an integer number (39354126).

Almost surely, 2^78708251 is an apocalyptic number.

78708251 is a deficient number, since it is larger than the sum of its proper divisors (1).

78708251 is an equidigital number, since it uses as much as digits as its factorization.

78708251 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 31360, while the sum is 38.

The square root of 78708251 is about 8871.7670731371. The cubic root of 78708251 is about 428.5551850616. Note that the first 3 decimals are identical.

The spelling of 78708251 in words is "seventy-eight million, seven hundred eight thousand, two hundred fifty-one".