90923681 has 2 divisors, whose sum is σ = 90923682. Its totient is φ = 90923680.

The previous prime is 90923647. The next prime is 90923687. The reversal of 90923681 is 18632909.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 74995600 + 15928081 = 8660^2 + 3991^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-90923681 is a prime.

It is a super-2 number, since 2×90923681² = 16534231533179522, which contains 22 as substring.

It is equal to p_5267495 and since 90923681 and 5267495 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 (90923687) 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, 45461840 + 45461841.

It is an arithmetic number, because the mean of its divisors is an integer number (45461841).

Almost surely, 2^90923681 is an apocalyptic number.

It is an amenable number.

90923681 is a deficient number, since it is larger than the sum of its proper divisors (1).

90923681 is an equidigital number, since it uses as much as digits as its factorization.

90923681 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 23328, while the sum is 38.

The square root of 90923681 is about 9535.3909725821. The cubic root of 90923681 is about 449.6683663577.

The spelling of 90923681 in words is "ninety million, nine hundred twenty-three thousand, six hundred eighty-one".