987105409 has 2 divisors, whose sum is σ = 987105410. Its totient is φ = 987105408.

The previous prime is 987105407. The next prime is 987105419. The reversal of 987105409 is 904501789.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 673921600 + 313183809 = 25960^2 + 17697^2 .

It is an emirp because it is prime and its reverse (904501789) is a distict prime.

It is a cyclic number.

It is not a de Polignac number, because 987105409 - 2¹ = 987105407 is a prime.

Together with 987105407, it forms a pair of twin primes.

It is not a weakly prime, because it can be changed into another prime (987105407) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 493552704 + 493552705.

It is an arithmetic number, because the mean of its divisors is an integer number (493552705).

Almost surely, 2^987105409 is an apocalyptic number.

It is an amenable number.

987105409 is a deficient number, since it is larger than the sum of its proper divisors (1).

987105409 is an equidigital number, since it uses as much as digits as its factorization.

987105409 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 90720, while the sum is 43.

The square root of 987105409 is about 31418.2337027402. The cubic root of 987105409 is about 995.6831950089.

The spelling of 987105409 in words is "nine hundred eighty-seven million, one hundred five thousand, four hundred nine".