78388313 has 2 divisors, whose sum is σ = 78388314. Its totient is φ = 78388312.

The previous prime is 78388283. The next prime is 78388333. The reversal of 78388313 is 31388387.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 61512649 + 16875664 = 7843^2 + 4108^2 .

It is an emirp because it is prime and its reverse (31388387) is a distict prime.

It is a cyclic number.

It is not a de Polignac number, because 78388313 - 2¹² = 78384217 is a prime.

It is a super-2 number, since 2×78388313² = 12289455229971938, which contains 22 as substring.

It is a Chen prime.

It is not a weakly prime, because it can be changed into another prime (78388333) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 39194156 + 39194157.

It is an arithmetic number, because the mean of its divisors is an integer number (39194157).

Almost surely, 2^78388313 is an apocalyptic number.

It is an amenable number.

78388313 is a deficient number, since it is larger than the sum of its proper divisors (1).

78388313 is an equidigital number, since it uses as much as digits as its factorization.

78388313 is an evil number, because the sum of its binary digits is even.

The product of its digits is 96768, while the sum is 41.

The square root of 78388313 is about 8853.7174678211. The cubic root of 78388313 is about 427.9737242582.

The spelling of 78388313 in words is "seventy-eight million, three hundred eighty-eight thousand, three hundred thirteen".