78351281 has 2 divisors, whose sum is σ = 78351282. Its totient is φ = 78351280.

The previous prime is 78351257. The next prime is 78351293. The reversal of 78351281 is 18215387.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 77176225 + 1175056 = 8785^2 + 1084^2 .

It is an emirp because it is prime and its reverse (18215387) is a distict prime.

It is a cyclic number.

It is not a de Polignac number, because 78351281 - 2¹⁴ = 78334897 is a prime.

It is a super-2 number, since 2×78351281² = 12277846468681922, which contains 22 as substring.

It is a Chen prime.

It is not a weakly prime, because it can be changed into another prime (78351781) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 39175640 + 39175641.

It is an arithmetic number, because the mean of its divisors is an integer number (39175641).

Almost surely, 2^78351281 is an apocalyptic number.

It is an amenable number.

78351281 is a deficient number, since it is larger than the sum of its proper divisors (1).

78351281 is an equidigital number, since it uses as much as digits as its factorization.

78351281 is an evil number, because the sum of its binary digits is even.

The product of its digits is 13440, while the sum is 35.

The square root of 78351281 is about 8851.6258958454. The cubic root of 78351281 is about 427.9063195701.

The spelling of 78351281 in words is "seventy-eight million, three hundred fifty-one thousand, two hundred eighty-one".