219638199857 has 2 divisors, whose sum is σ = 219638199858. Its totient is φ = 219638199856.

The previous prime is 219638199811. The next prime is 219638199917. The reversal of 219638199857 is 758991836912.

It is a happy number.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 197558914576 + 22079285281 = 444476^2 + 148591^2 .

It is a cyclic number.

It is not a de Polignac number, because 219638199857 - 2²⁸ = 219369764401 is a prime.

It is not a weakly prime, because it can be changed into another prime (219638192857) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 109819099928 + 109819099929.

It is an arithmetic number, because the mean of its divisors is an integer number (109819099929).

Almost surely, 2^219638199857 is an apocalyptic number.

It is an amenable number.

219638199857 is a deficient number, since it is larger than the sum of its proper divisors (1).

219638199857 is an equidigital number, since it uses as much as digits as its factorization.

219638199857 is an evil number, because the sum of its binary digits is even.

The product of its digits is 58786560, while the sum is 68.

The spelling of 219638199857 in words is "two hundred nineteen billion, six hundred thirty-eight million, one hundred ninety-nine thousand, eight hundred fifty-seven".