90368981 has 2 divisors, whose sum is σ = 90368982. Its totient is φ = 90368980.

The previous prime is 90368977. The next prime is 90368987. The reversal of 90368981 is 18986309.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 85396081 + 4972900 = 9241^2 + 2230^2 .

It is an emirp because it is prime and its reverse (18986309) is a distict prime.

It is a cyclic number.

It is not a de Polignac number, because 90368981 - 2² = 90368977 is a prime.

It is a super-2 number, since 2×90368981² = 16333105453956722, 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 (90368987) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 45184490 + 45184491.

It is an arithmetic number, because the mean of its divisors is an integer number (45184491).

Almost surely, 2^90368981 is an apocalyptic number.

It is an amenable number.

90368981 is a deficient number, since it is larger than the sum of its proper divisors (1).

90368981 is an equidigital number, since it uses as much as digits as its factorization.

90368981 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 90368981 is about 9506.2600953267. The cubic root of 90368981 is about 448.7520667290.

The spelling of 90368981 in words is "ninety million, three hundred sixty-eight thousand, nine hundred eighty-one".