9990557 has 2 divisors, whose sum is σ = 9990558. Its totient is φ = 9990556.

The previous prime is 9990551. The next prime is 9990569. The reversal of 9990557 is 7550999.

9990557 is digitally balanced in base 2 and base 3, because in such bases it contains all the possibile digits an equal number of times.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 7513081 + 2477476 = 2741^2 + 1574^2 .

It is a cyclic number.

It is not a de Polignac number, because 9990557 - 2⁶ = 9990493 is a prime.

It is a super-2 number, since 2×9990557² = 199622458340498, which contains 22 as substring.

It is a Chen prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (9990551) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 4995278 + 4995279.

It is an arithmetic number, because the mean of its divisors is an integer number (4995279).

Almost surely, 2^9990557 is an apocalyptic number.

It is an amenable number.

9990557 is a deficient number, since it is larger than the sum of its proper divisors (1).

9990557 is an equidigital number, since it uses as much as digits as its factorization.

9990557 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 127575, while the sum is 44.

The square root of 9990557 is about 3160.7842381283. The cubic root of 9990557 is about 215.3756332237.

The spelling of 9990557 in words is "nine million, nine hundred ninety thousand, five hundred fifty-seven".