7999780057 has 2 divisors, whose sum is σ = 7999780058. Its totient is φ = 7999780056.

The previous prime is 7999779979. The next prime is 7999780079. The reversal of 7999780057 is 7500879997.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 5990140816 + 2009639241 = 77396^2 + 44829^2 .

It is a cyclic number.

It is not a de Polignac number, because 7999780057 - 2⁷ = 7999779929 is a prime.

It is a junction number, because it is equal to n+sod(n) for n = 7999779977 and 7999780004.

It is not a weakly prime, because it can be changed into another prime (7999780097) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 3999890028 + 3999890029.

It is an arithmetic number, because the mean of its divisors is an integer number (3999890029).

Almost surely, 2^7999780057 is an apocalyptic number.

It is an amenable number.

7999780057 is a deficient number, since it is larger than the sum of its proper divisors (1).

7999780057 is an equidigital number, since it uses as much as digits as its factorization.

7999780057 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 10001880, while the sum is 61.

The square root of 7999780057 is about 89441.4895727928. The cubic root of 7999780057 is about 1999.9816712487.

The spelling of 7999780057 in words is "seven billion, nine hundred ninety-nine million, seven hundred eighty thousand, fifty-seven".