78701999 has 2 divisors, whose sum is σ = 78702000. Its totient is φ = 78701998.

The previous prime is 78701981. The next prime is 78702007. The reversal of 78701999 is 99910787.

It is a strong prime.

It is a cyclic number.

It is not a de Polignac number, because 78701999 - 2¹⁶ = 78636463 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (78709999) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 39350999 + 39351000.

It is an arithmetic number, because the mean of its divisors is an integer number (39351000).

Almost surely, 2^78701999 is an apocalyptic number.

78701999 is a deficient number, since it is larger than the sum of its proper divisors (1).

78701999 is an equidigital number, since it uses as much as digits as its factorization.

78701999 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 285768, while the sum is 50.

The square root of 78701999 is about 8871.4147124345. The cubic root of 78701999 is about 428.5438376788.

The spelling of 78701999 in words is "seventy-eight million, seven hundred one thousand, nine hundred ninety-nine".