90858749 has 2 divisors, whose sum is σ = 90858750. Its totient is φ = 90858748.

The previous prime is 90858739. The next prime is 90858751. The reversal of 90858749 is 94785809.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 67404100 + 23454649 = 8210^2 + 4843^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-90858749 is a prime.

It is a Sophie Germain prime.

Together with 90858751, it forms a pair of twin primes.

It is a Chen prime.

It is a Curzon number.

It is a junction number, because it is equal to n+sod(n) for n = 90858697 and 90858706.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (90858739) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 45429374 + 45429375.

It is an arithmetic number, because the mean of its divisors is an integer number (45429375).

Almost surely, 2^90858749 is an apocalyptic number.

It is an amenable number.

90858749 is a deficient number, since it is larger than the sum of its proper divisors (1).

90858749 is an equidigital number, since it uses as much as digits as its factorization.

90858749 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 725760, while the sum is 50.

The square root of 90858749 is about 9531.9855748947. The cubic root of 90858749 is about 449.5612992026.

It can be divided in two parts, 9085874 and 9, that multiplied together give a triangular number (81772866 = T₁₂₇₈₈).

The spelling of 90858749 in words is "ninety million, eight hundred fifty-eight thousand, seven hundred forty-nine".