78274839689 has 2 divisors, whose sum is σ = 78274839690. Its totient is φ = 78274839688.

The previous prime is 78274839679. The next prime is 78274839691. The reversal of 78274839689 is 98693847287.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 54572697664 + 23702142025 = 233608^2 + 153955^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-78274839689 is a prime.

It is a super-2 number, since 2×78274839689² (a number of 23 digits) contains 22 as substring.

Together with 78274839691, it forms a pair of twin primes.

It is a Chen prime.

It is not a weakly prime, because it can be changed into another prime (78274839679) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 39137419844 + 39137419845.

It is an arithmetic number, because the mean of its divisors is an integer number (39137419845).

Almost surely, 2^78274839689 is an apocalyptic number.

It is an amenable number.

78274839689 is a deficient number, since it is larger than the sum of its proper divisors (1).

78274839689 is an equidigital number, since it uses as much as digits as its factorization.

78274839689 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 292626432, while the sum is 71.

The spelling of 78274839689 in words is "seventy-eight billion, two hundred seventy-four million, eight hundred thirty-nine thousand, six hundred eighty-nine".