77138513 has 2 divisors, whose sum is σ = 77138514. Its totient is φ = 77138512.

The previous prime is 77138497. The next prime is 77138519. The reversal of 77138513 is 31583177.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 64128064 + 13010449 = 8008^2 + 3607^2 .

It is a cyclic number.

It is not a de Polignac number, because 77138513 - 2⁴ = 77138497 is a prime.

It is a Sophie Germain prime.

It is a Curzon number.

It is not a weakly prime, because it can be changed into another prime (77138519) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 38569256 + 38569257.

It is an arithmetic number, because the mean of its divisors is an integer number (38569257).

Almost surely, 2^77138513 is an apocalyptic number.

It is an amenable number.

77138513 is a deficient number, since it is larger than the sum of its proper divisors (1).

77138513 is an equidigital number, since it uses as much as digits as its factorization.

77138513 is an evil number, because the sum of its binary digits is even.

The product of its digits is 17640, while the sum is 35.

The square root of 77138513 is about 8782.8533518441. The cubic root of 77138513 is about 425.6870327251.

The spelling of 77138513 in words is "seventy-seven million, one hundred thirty-eight thousand, five hundred thirteen".