47487809 has 2 divisors, whose sum is σ = 47487810. Its totient is φ = 47487808.

The previous prime is 47487779. The next prime is 47487827. The reversal of 47487809 is 90878474.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 38093584 + 9394225 = 6172^2 + 3065^2 .

It is a cyclic number.

It is not a de Polignac number, because 47487809 - 2¹² = 47483713 is a prime.

It is a Sophie Germain prime.

It is a Curzon number.

It is not a weakly prime, because it can be changed into another prime (47487889) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 23743904 + 23743905.

It is an arithmetic number, because the mean of its divisors is an integer number (23743905).

Almost surely, 2^47487809 is an apocalyptic number.

It is an amenable number.

47487809 is a deficient number, since it is larger than the sum of its proper divisors (1).

47487809 is an equidigital number, since it uses as much as digits as its factorization.

47487809 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 451584, while the sum is 47.

The square root of 47487809 is about 6891.1398911936. The cubic root of 47487809 is about 362.1268366017.

The spelling of 47487809 in words is "forty-seven million, four hundred eighty-seven thousand, eight hundred nine".