78577393 has 2 divisors, whose sum is σ = 78577394. Its totient is φ = 78577392.

The previous prime is 78577391. The next prime is 78577403. The reversal of 78577393 is 39377587.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 40347904 + 38229489 = 6352^2 + 6183^2 .

It is a cyclic number.

It is not a de Polignac number, because 78577393 - 2¹ = 78577391 is a prime.

Together with 78577391, it forms a pair of twin primes.

It is not a weakly prime, because it can be changed into another prime (78577391) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 39288696 + 39288697.

It is an arithmetic number, because the mean of its divisors is an integer number (39288697).

Almost surely, 2^78577393 is an apocalyptic number.

It is an amenable number.

78577393 is a deficient number, since it is larger than the sum of its proper divisors (1).

78577393 is an equidigital number, since it uses as much as digits as its factorization.

78577393 is an evil number, because the sum of its binary digits is even.

The product of its digits is 1111320, while the sum is 49.

The square root of 78577393 is about 8864.3890370403. The cubic root of 78577393 is about 428.3175522792.

The spelling of 78577393 in words is "seventy-eight million, five hundred seventy-seven thousand, three hundred ninety-three".