9951558857 has 2 divisors, whose sum is σ = 9951558858. Its totient is φ = 9951558856.

The previous prime is 9951558839. The next prime is 9951558893. The reversal of 9951558857 is 7588551599.

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., 7811201161 + 2140357696 = 88381^2 + 46264^2 .

It is a cyclic number.

It is not a de Polignac number, because 9951558857 - 2¹⁸ = 9951296713 is a prime.

It is a self number, because there is not a number n which added to its sum of digits gives 9951558857.

It is not a weakly prime, because it can be changed into another prime (9951558257) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 4975779428 + 4975779429.

It is an arithmetic number, because the mean of its divisors is an integer number (4975779429).

Almost surely, 2^9951558857 is an apocalyptic number.

It is an amenable number.

9951558857 is a deficient number, since it is larger than the sum of its proper divisors (1).

9951558857 is an equidigital number, since it uses as much as digits as its factorization.

9951558857 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 22680000, while the sum is 62.

The square root of 9951558857 is about 99757.5002543668. The cubic root of 9951558857 is about 2150.9502817064.

The spelling of 9951558857 in words is "nine billion, nine hundred fifty-one million, five hundred fifty-eight thousand, eight hundred fifty-seven".