78451231 has 2 divisors, whose sum is σ = 78451232. Its totient is φ = 78451230.

The previous prime is 78451213. The next prime is 78451271. The reversal of 78451231 is 13215487.

Together with previous prime (78451213) it forms an Ormiston pair, because they use the same digits, order apart.

It is a weak prime.

It is a cyclic number.

It is not a de Polignac number, because 78451231 - 2⁵ = 78451199 is a prime.

It is a super-2 number, since 2×78451231² = 12309191290830722, which contains 22 as substring.

It is a junction number, because it is equal to n+sod(n) for n = 78451193 and 78451202.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (78451271) by changing a digit.

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

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 39225615 + 39225616.

It is an arithmetic number, because the mean of its divisors is an integer number (39225616).

Almost surely, 2^78451231 is an apocalyptic number.

78451231 is a deficient number, since it is larger than the sum of its proper divisors (1).

78451231 is an equidigital number, since it uses as much as digits as its factorization.

78451231 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 6720, while the sum is 31.

The square root of 78451231 is about 8857.2699518531. The cubic root of 78451231 is about 428.0881973160.

It can be divided in two parts, 78451 and 231, that multiplied together give a palindrome (18122181).

The spelling of 78451231 in words is "seventy-eight million, four hundred fifty-one thousand, two hundred thirty-one".