87773209 has 2 divisors, whose sum is σ = 87773210. Its totient is φ = 87773208.

The previous prime is 87773207. The next prime is 87773233. The reversal of 87773209 is 90237778.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 66585600 + 21187609 = 8160^2 + 4603^2 .

It is a cyclic number.

It is not a de Polignac number, because 87773209 - 2¹ = 87773207 is a prime.

Together with 87773207, it forms a pair of twin primes.

It is not a weakly prime, because it can be changed into another prime (87773207) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 43886604 + 43886605.

It is an arithmetic number, because the mean of its divisors is an integer number (43886605).

Almost surely, 2^87773209 is an apocalyptic number.

It is an amenable number.

87773209 is a deficient number, since it is larger than the sum of its proper divisors (1).

87773209 is an equidigital number, since it uses as much as digits as its factorization.

87773209 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 148176, while the sum is 43.

The square root of 87773209 is about 9368.7357204694. The cubic root of 87773209 is about 444.4135843411.

The spelling of 87773209 in words is "eighty-seven million, seven hundred seventy-three thousand, two hundred nine".