87290909 has 2 divisors, whose sum is σ = 87290910. Its totient is φ = 87290908.

The previous prime is 87290873. The next prime is 87290941. The reversal of 87290909 is 90909278.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 79744900 + 7546009 = 8930^2 + 2747^2 .

It is a cyclic number.

It is not a de Polignac number, because 87290909 - 2⁸ = 87290653 is a prime.

It is a Sophie Germain prime.

It is an alternating number because its digits alternate between even and odd.

It is a Curzon number.

It is a self number, because there is not a number n which added to its sum of digits gives 87290909.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (87290969) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 43645454 + 43645455.

It is an arithmetic number, because the mean of its divisors is an integer number (43645455).

Almost surely, 2^87290909 is an apocalyptic number.

It is an amenable number.

87290909 is a deficient number, since it is larger than the sum of its proper divisors (1).

87290909 is an equidigital number, since it uses as much as digits as its factorization.

87290909 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 81648, while the sum is 44.

The square root of 87290909 is about 9342.9603980751. The cubic root of 87290909 is about 443.5980945636.

The spelling of 87290909 in words is "eighty-seven million, two hundred ninety thousand, nine hundred nine".