63978857 has 2 divisors, whose sum is σ = 63978858. Its totient is φ = 63978856.

The previous prime is 63978853. The next prime is 63978899. The reversal of 63978857 is 75887936.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 35473936 + 28504921 = 5956^2 + 5339^2 .

It is a cyclic number.

It is not a de Polignac number, because 63978857 - 2² = 63978853 is a prime.

It is a junction number, because it is equal to n+sod(n) for n = 63978799 and 63978808.

It is not a weakly prime, because it can be changed into another prime (63978853) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 31989428 + 31989429.

It is an arithmetic number, because the mean of its divisors is an integer number (31989429).

Almost surely, 2^63978857 is an apocalyptic number.

It is an amenable number.

63978857 is a deficient number, since it is larger than the sum of its proper divisors (1).

63978857 is an equidigital number, since it uses as much as digits as its factorization.

63978857 is an evil number, because the sum of its binary digits is even.

The product of its digits is 2540160, while the sum is 53.

The square root of 63978857 is about 7998.6784533447. The cubic root of 63978857 is about 399.9559472319.

The spelling of 63978857 in words is "sixty-three million, nine hundred seventy-eight thousand, eight hundred fifty-seven".