78247331 has 2 divisors, whose sum is σ = 78247332. Its totient is φ = 78247330.

The previous prime is 78247321. The next prime is 78247343. The reversal of 78247331 is 13374287.

It is a weak prime.

It is a cyclic number.

It is not a de Polignac number, because 78247331 - 2¹⁴ = 78230947 is a prime.

It is a super-2 number, since 2×78247331² = 12245289617247122, which contains 22 as substring.

It is a Chen prime.

It is a junction number, because it is equal to n+sod(n) for n = 78247291 and 78247300.

It is not a weakly prime, because it can be changed into another prime (78247321) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 39123665 + 39123666.

It is an arithmetic number, because the mean of its divisors is an integer number (39123666).

Almost surely, 2^78247331 is an apocalyptic number.

78247331 is a deficient number, since it is larger than the sum of its proper divisors (1).

78247331 is an equidigital number, since it uses as much as digits as its factorization.

78247331 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 28224, while the sum is 35.

The square root of 78247331 is about 8845.7521443911. The cubic root of 78247331 is about 427.7169989148.

The spelling of 78247331 in words is "seventy-eight million, two hundred forty-seven thousand, three hundred thirty-one".