78923513 has 2 divisors, whose sum is σ = 78923514. Its totient is φ = 78923512.

The previous prime is 78923501. The next prime is 78923527. The reversal of 78923513 is 31532987.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 44782864 + 34140649 = 6692^2 + 5843^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-78923513 is a prime.

It is a super-2 number, since 2×78923513² = 12457841808522338, which contains 22 as substring.

It is not a weakly prime, because it can be changed into another prime (78923113) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 39461756 + 39461757.

It is an arithmetic number, because the mean of its divisors is an integer number (39461757).

Almost surely, 2^78923513 is an apocalyptic number.

It is an amenable number.

78923513 is a deficient number, since it is larger than the sum of its proper divisors (1).

78923513 is an equidigital number, since it uses as much as digits as its factorization.

78923513 is an evil number, because the sum of its binary digits is even.

The product of its digits is 45360, while the sum is 38.

The square root of 78923513 is about 8883.8906454323. The cubic root of 78923513 is about 428.9455197125.

The spelling of 78923513 in words is "seventy-eight million, nine hundred twenty-three thousand, five hundred thirteen".