90865849 has 2 divisors, whose sum is σ = 90865850. Its totient is φ = 90865848.

The previous prime is 90865843. The next prime is 90865883. The reversal of 90865849 is 94856809.

It is a happy number.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 87553449 + 3312400 = 9357^2 + 1820^2 .

It is an emirp because it is prime and its reverse (94856809) is a distict prime.

It is a cyclic number.

It is not a de Polignac number, because 90865849 - 2²¹ = 88768697 is a prime.

It is not a weakly prime, because it can be changed into another prime (90865843) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 45432924 + 45432925.

It is an arithmetic number, because the mean of its divisors is an integer number (45432925).

Almost surely, 2^90865849 is an apocalyptic number.

It is an amenable number.

90865849 is a deficient number, since it is larger than the sum of its proper divisors (1).

90865849 is an equidigital number, since it uses as much as digits as its factorization.

90865849 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 622080, while the sum is 49.

The square root of 90865849 is about 9532.3579978933. The cubic root of 90865849 is about 449.5730089614.

The spelling of 90865849 in words is "ninety million, eight hundred sixty-five thousand, eight hundred forty-nine".