78139903 has 2 divisors, whose sum is σ = 78139904. Its totient is φ = 78139902.

The previous prime is 78139883. The next prime is 78139931. The reversal of 78139903 is 30993187.

It is a weak prime.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-78139903 is a prime.

It is a super-2 number, since 2×78139903² = 12211688881698818, which contains 22 as substring.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (78139703) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 39069951 + 39069952.

It is an arithmetic number, because the mean of its divisors is an integer number (39069952).

Almost surely, 2^78139903 is an apocalyptic number.

78139903 is a deficient number, since it is larger than the sum of its proper divisors (1).

78139903 is an equidigital number, since it uses as much as digits as its factorization.

78139903 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 40824, while the sum is 40.

The square root of 78139903 is about 8839.6777656202. The cubic root of 78139903 is about 427.5211676306.

The spelling of 78139903 in words is "seventy-eight million, one hundred thirty-nine thousand, nine hundred three".