78770885749 has 2 divisors, whose sum is σ = 78770885750. Its totient is φ = 78770885748.

The previous prime is 78770885707. The next prime is 78770885777. The reversal of 78770885749 is 94758807787.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 47324956849 + 31445928900 = 217543^2 + 177330^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-78770885749 is a prime.

It is a super-2 number, since 2×78770885749² (a number of 23 digits) contains 22 as substring.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (78770885549) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 39385442874 + 39385442875.

It is an arithmetic number, because the mean of its divisors is an integer number (39385442875).

Almost surely, 2^78770885749 is an apocalyptic number.

It is an amenable number.

78770885749 is a deficient number, since it is larger than the sum of its proper divisors (1).

78770885749 is an equidigital number, since it uses as much as digits as its factorization.

78770885749 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 221276160, while the sum is 70.

The spelling of 78770885749 in words is "seventy-eight billion, seven hundred seventy million, eight hundred eighty-five thousand, seven hundred forty-nine".