90120557 has 2 divisors, whose sum is σ = 90120558. Its totient is φ = 90120556.

The previous prime is 90120539. The next prime is 90120577. The reversal of 90120557 is 75502109.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 54848836 + 35271721 = 7406^2 + 5939^2 .

It is a cyclic number.

It is not a de Polignac number, because 90120557 - 2⁸ = 90120301 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 (90120577) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 45060278 + 45060279.

It is an arithmetic number, because the mean of its divisors is an integer number (45060279).

Almost surely, 2^90120557 is an apocalyptic number.

It is an amenable number.

90120557 is a deficient number, since it is larger than the sum of its proper divisors (1).

90120557 is an equidigital number, since it uses as much as digits as its factorization.

90120557 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 3150, while the sum is 29.

The square root of 90120557 is about 9493.1847659255. The cubic root of 90120557 is about 448.3404834184.

The spelling of 90120557 in words is "ninety million, one hundred twenty thousand, five hundred fifty-seven".