39987066857 has 2 divisors, whose sum is σ = 39987066858. Its totient is φ = 39987066856.

The previous prime is 39987066809. The next prime is 39987066871. The reversal of 39987066857 is 75866078993.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 38445797776 + 1541269081 = 196076^2 + 39259^2 .

It is a cyclic number.

It is not a de Polignac number, because 39987066857 - 2⁶ = 39987066793 is a prime.

It is not a weakly prime, because it can be changed into another prime (39987066877) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 19993533428 + 19993533429.

It is an arithmetic number, because the mean of its divisors is an integer number (19993533429).

Almost surely, 2^39987066857 is an apocalyptic number.

It is an amenable number.

39987066857 is a deficient number, since it is larger than the sum of its proper divisors (1).

39987066857 is an equidigital number, since it uses as much as digits as its factorization.

39987066857 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 137168640, while the sum is 68.

The spelling of 39987066857 in words is "thirty-nine billion, nine hundred eighty-seven million, sixty-six thousand, eight hundred fifty-seven".