998951557 has 2 divisors, whose sum is σ = 998951558. Its totient is φ = 998951556.

The previous prime is 998951521. The next prime is 998951561. The reversal of 998951557 is 755159899.

998951557 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 998939236 + 12321 = 31606^2 + 111^2 .

It is a cyclic number.

It is not a de Polignac number, because 998951557 - 2¹¹ = 998949509 is a prime.

It is a Chen prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (998951587) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 499475778 + 499475779.

It is an arithmetic number, because the mean of its divisors is an integer number (499475779).

Almost surely, 2^998951557 is an apocalyptic number.

It is an amenable number.

998951557 is a deficient number, since it is larger than the sum of its proper divisors (1).

998951557 is an equidigital number, since it uses as much as digits as its factorization.

998951557 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 5103000, while the sum is 58.

The square root of 998951557 is about 31606.1949149213. The cubic root of 998951557 is about 999.6503967918.

The spelling of 998951557 in words is "nine hundred ninety-eight million, nine hundred fifty-one thousand, five hundred fifty-seven".