90847681 has 2 divisors, whose sum is σ = 90847682. Its totient is φ = 90847680.

The previous prime is 90847667. The next prime is 90847699. The reversal of 90847681 is 18674809.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 66994225 + 23853456 = 8185^2 + 4884^2 .

It is an emirp because it is prime and its reverse (18674809) is a distict prime.

It is a cyclic number.

It is not a de Polignac number, because 90847681 - 2⁵ = 90847649 is a prime.

It is a super-2 number, since 2×90847681² = 16506602286155522, which contains 22 as substring.

It is not a weakly prime, because it can be changed into another prime (90847661) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 45423840 + 45423841.

It is an arithmetic number, because the mean of its divisors is an integer number (45423841).

Almost surely, 2^90847681 is an apocalyptic number.

It is an amenable number.

90847681 is a deficient number, since it is larger than the sum of its proper divisors (1).

90847681 is an equidigital number, since it uses as much as digits as its factorization.

90847681 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 96768, while the sum is 43.

The square root of 90847681 is about 9531.4049856252. The cubic root of 90847681 is about 449.5430439564.

The spelling of 90847681 in words is "ninety million, eight hundred forty-seven thousand, six hundred eighty-one".