8077780397 has 2 divisors, whose sum is σ = 8077780398. Its totient is φ = 8077780396.

The previous prime is 8077780387. The next prime is 8077780409. The reversal of 8077780397 is 7930877708.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 4974621961 + 3103158436 = 70531^2 + 55706^2 .

It is a cyclic number.

It is not a de Polignac number, because 8077780397 - 2¹⁶ = 8077714861 is a prime.

It is a super-2 number, since 2×8077780397² (a number of 21 digits) contains 22 as substring.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (8077780307) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 4038890198 + 4038890199.

It is an arithmetic number, because the mean of its divisors is an integer number (4038890199).

Almost surely, 2^8077780397 is an apocalyptic number.

It is an amenable number.

8077780397 is a deficient number, since it is larger than the sum of its proper divisors (1).

8077780397 is an equidigital number, since it uses as much as digits as its factorization.

8077780397 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 4148928, while the sum is 56.

The square root of 8077780397 is about 89876.4729893202. The cubic root of 8077780397 is about 2006.4608062673.

The spelling of 8077780397 in words is "eight billion, seventy-seven million, seven hundred eighty thousand, three hundred ninety-seven".