78413281 has 2 divisors, whose sum is σ = 78413282. Its totient is φ = 78413280.

The previous prime is 78413261. The next prime is 78413287. The reversal of 78413281 is 18231487.

It is a happy number.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 78163281 + 250000 = 8841^2 + 500^2 .

It is a cyclic number.

It is not a de Polignac number, because 78413281 - 2¹⁵ = 78380513 is a prime.

It is a super-2 number, since 2×78413281² = 12297285274369922, which contains 22 as substring.

It is not a weakly prime, because it can be changed into another prime (78413287) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 39206640 + 39206641.

It is an arithmetic number, because the mean of its divisors is an integer number (39206641).

Almost surely, 2^78413281 is an apocalyptic number.

It is an amenable number.

78413281 is a deficient number, since it is larger than the sum of its proper divisors (1).

78413281 is an equidigital number, since it uses as much as digits as its factorization.

78413281 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 10752, while the sum is 34.

The square root of 78413281 is about 8855.1273847416. The cubic root of 78413281 is about 428.0191583848.

The spelling of 78413281 in words is "seventy-eight million, four hundred thirteen thousand, two hundred eighty-one".