78209903 has 2 divisors, whose sum is σ = 78209904. Its totient is φ = 78209902.

The previous prime is 78209863. The next prime is 78209939. The reversal of 78209903 is 30990287.

It is a strong prime.

It is a cyclic number.

It is not a de Polignac number, because 78209903 - 2¹² = 78205807 is a prime.

It is a super-2 number, since 2×78209903² = 12233577854538818, which contains 22 as substring.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (78209953) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 39104951 + 39104952.

It is an arithmetic number, because the mean of its divisors is an integer number (39104952).

Almost surely, 2^78209903 is an apocalyptic number.

78209903 is a deficient number, since it is larger than the sum of its proper divisors (1).

78209903 is an equidigital number, since it uses as much as digits as its factorization.

78209903 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 27216, while the sum is 38.

The square root of 78209903 is about 8843.6362996225. The cubic root of 78209903 is about 427.6487914979.

The spelling of 78209903 in words is "seventy-eight million, two hundred nine thousand, nine hundred three".