7857782057 has 2 divisors, whose sum is σ = 7857782058. Its totient is φ = 7857782056.

The previous prime is 7857781993. The next prime is 7857782131. The reversal of 7857782057 is 7502877587.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 6411044761 + 1446737296 = 80069^2 + 38036^2 .

It is a cyclic number.

It is not a de Polignac number, because 7857782057 - 2⁶ = 7857781993 is a prime.

It is a super-2 number, since 2×7857782057² (a number of 21 digits) contains 22 as substring.

It is a junction number, because it is equal to n+sod(n) for n = 7857781993 and 7857782011.

It is not a weakly prime, because it can be changed into another prime (7857782357) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 3928891028 + 3928891029.

It is an arithmetic number, because the mean of its divisors is an integer number (3928891029).

Almost surely, 2^7857782057 is an apocalyptic number.

It is an amenable number.

7857782057 is a deficient number, since it is larger than the sum of its proper divisors (1).

7857782057 is an equidigital number, since it uses as much as digits as its factorization.

7857782057 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 7683200, while the sum is 56.

The square root of 7857782057 is about 88644.1315429284. The cubic root of 7857782057 is about 1988.0775738527.

The spelling of 7857782057 in words is "seven billion, eight hundred fifty-seven million, seven hundred eighty-two thousand, fifty-seven".