99998557 has 2 divisors, whose sum is σ = 99998558. Its totient is φ = 99998556.

The previous prime is 99998551. The next prime is 99998603. The reversal of 99998557 is 75589999.

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., 92659876 + 7338681 = 9626^2 + 2709^2 .

It is a cyclic number.

It is not a de Polignac number, because 99998557 - 2⁷ = 99998429 is a prime.

It is a super-2 number, since 2×99998557² = 19999422804164498, which contains 22 as substring.

It is a junction number, because it is equal to n+sod(n) for n = 99998495 and 99998504.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (99998551) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 49999278 + 49999279.

It is an arithmetic number, because the mean of its divisors is an integer number (49999279).

Almost surely, 2^99998557 is an apocalyptic number.

It is an amenable number.

99998557 is a deficient number, since it is larger than the sum of its proper divisors (1).

99998557 is an equidigital number, since it uses as much as digits as its factorization.

99998557 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 9185400, while the sum is 61.

The square root of 99998557 is about 9999.9278497397. The cubic root of 99998557 is about 464.1566507463.

The spelling of 99998557 in words is "ninety-nine million, nine hundred ninety-eight thousand, five hundred fifty-seven".