90016681 has 2 divisors, whose sum is σ = 90016682. Its totient is φ = 90016680.

The previous prime is 90016651. The next prime is 90016697. The reversal of 90016681 is 18661009.

It is a happy number.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 78854400 + 11162281 = 8880^2 + 3341^2 .

It is an emirp because it is prime and its reverse (18661009) is a distict prime.

It is a cyclic number.

It is not a de Polignac number, because 90016681 - 2²⁵ = 56462249 is a prime.

It is a super-2 number, since 2×90016681² = 16206005716511522, which contains 22 as substring.

It is equal to p_5217871 and since 90016681 and 5217871 have the same sum of digits, it is a Honaker prime.

It is not a weakly prime, because it can be changed into another prime (90016651) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 45008340 + 45008341.

It is an arithmetic number, because the mean of its divisors is an integer number (45008341).

Almost surely, 2^90016681 is an apocalyptic number.

It is an amenable number.

90016681 is a deficient number, since it is larger than the sum of its proper divisors (1).

90016681 is an equidigital number, since it uses as much as digits as its factorization.

90016681 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 2592, while the sum is 31.

The square root of 90016681 is about 9487.7121056659. The cubic root of 90016681 is about 448.1681597278.

The spelling of 90016681 in words is "ninety million, sixteen thousand, six hundred eighty-one".