78538477 has 2 divisors, whose sum is σ = 78538478. Its totient is φ = 78538476.

The previous prime is 78538463. The next prime is 78538483. The reversal of 78538477 is 77483587.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 78393316 + 145161 = 8854^2 + 381^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-78538477 is a prime.

It is a Chen prime.

It is a self number, because there is not a number n which added to its sum of digits gives 78538477.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (78538777) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 39269238 + 39269239.

It is an arithmetic number, because the mean of its divisors is an integer number (39269239).

Almost surely, 2^78538477 is an apocalyptic number.

It is an amenable number.

78538477 is a deficient number, since it is larger than the sum of its proper divisors (1).

78538477 is an equidigital number, since it uses as much as digits as its factorization.

78538477 is an evil number, because the sum of its binary digits is even.

The product of its digits is 1317120, while the sum is 49.

The square root of 78538477 is about 8862.1936900521. The cubic root of 78538477 is about 428.2468315214.

The spelling of 78538477 in words is "seventy-eight million, five hundred thirty-eight thousand, four hundred seventy-seven".