78347974361 has 2 divisors, whose sum is σ = 78347974362. Its totient is φ = 78347974360.

The previous prime is 78347974357. The next prime is 78347974493. The reversal of 78347974361 is 16347974387.

It is a happy number.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 68014032025 + 10333942336 = 260795^2 + 101656^2 .

It is a cyclic number.

It is not a de Polignac number, because 78347974361 - 2² = 78347974357 is a prime.

It is a super-2 number, since 2×78347974361² (a number of 23 digits) contains 22 as substring.

It is a self number, because there is not a number n which added to its sum of digits gives 78347974361.

It is not a weakly prime, because it can be changed into another prime (78347974301) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 39173987180 + 39173987181.

It is an arithmetic number, because the mean of its divisors is an integer number (39173987181).

Almost surely, 2^78347974361 is an apocalyptic number.

It is an amenable number.

78347974361 is a deficient number, since it is larger than the sum of its proper divisors (1).

78347974361 is an equidigital number, since it uses as much as digits as its factorization.

78347974361 is an evil number, because the sum of its binary digits is even.

The product of its digits is 21337344, while the sum is 59.

The spelling of 78347974361 in words is "seventy-eight billion, three hundred forty-seven million, nine hundred seventy-four thousand, three hundred sixty-one".