75987409 has 2 divisors, whose sum is σ = 75987410. Its totient is φ = 75987408.

The previous prime is 75987397. The next prime is 75987449. The reversal of 75987409 is 90478957.

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., 72301009 + 3686400 = 8503^2 + 1920^2 .

It is a cyclic number.

It is not a de Polignac number, because 75987409 - 2¹⁹ = 75463121 is a prime.

It is a Chen prime.

It is not a weakly prime, because it can be changed into another prime (75987449) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 37993704 + 37993705.

It is an arithmetic number, because the mean of its divisors is an integer number (37993705).

Almost surely, 2^75987409 is an apocalyptic number.

It is an amenable number.

75987409 is a deficient number, since it is larger than the sum of its proper divisors (1).

75987409 is an equidigital number, since it uses as much as digits as its factorization.

75987409 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 635040, while the sum is 49.

The square root of 75987409 is about 8717.0757137930. The cubic root of 75987409 is about 423.5589653552.

The spelling of 75987409 in words is "seventy-five million, nine hundred eighty-seven thousand, four hundred nine".