90618389 has 2 divisors, whose sum is σ = 90618390. Its totient is φ = 90618388.

The previous prime is 90618379. The next prime is 90618401. The reversal of 90618389 is 98381609.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 65448100 + 25170289 = 8090^2 + 5017^2 .

It is an emirp because it is prime and its reverse (98381609) is a distict prime.

It is a cyclic number.

It is not a de Polignac number, because 90618389 - 2²⁰ = 89569813 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (90618379) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 45309194 + 45309195.

It is an arithmetic number, because the mean of its divisors is an integer number (45309195).

Almost surely, 2^90618389 is an apocalyptic number.

It is an amenable number.

90618389 is a deficient number, since it is larger than the sum of its proper divisors (1).

90618389 is an equidigital number, since it uses as much as digits as its factorization.

90618389 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 93312, while the sum is 44.

The square root of 90618389 is about 9519.3691492661. The cubic root of 90618389 is about 449.1645222255.

The spelling of 90618389 in words is "ninety million, six hundred eighteen thousand, three hundred eighty-nine".