78432881 has 2 divisors, whose sum is σ = 78432882. Its totient is φ = 78432880.

The previous prime is 78432839. The next prime is 78432899. The reversal of 78432881 is 18823487.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 71250481 + 7182400 = 8441^2 + 2680^2 .

It is a cyclic number.

It is not a de Polignac number, because 78432881 - 2²⁶ = 11324017 is a prime.

It is a super-2 number, since 2×78432881² = 12303433643920322, which contains 22 as substring.

It is not a weakly prime, because it can be changed into another prime (78432281) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a good prime.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 39216440 + 39216441.

It is an arithmetic number, because the mean of its divisors is an integer number (39216441).

Almost surely, 2^78432881 is an apocalyptic number.

It is an amenable number.

78432881 is a deficient number, since it is larger than the sum of its proper divisors (1).

78432881 is an equidigital number, since it uses as much as digits as its factorization.

78432881 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 86016, while the sum is 41.

The square root of 78432881 is about 8856.2340190399. The cubic root of 78432881 is about 428.0548176359.

The spelling of 78432881 in words is "seventy-eight million, four hundred thirty-two thousand, eight hundred eighty-one".