47918509 has 2 divisors, whose sum is σ = 47918510. Its totient is φ = 47918508.

The previous prime is 47918503. The next prime is 47918531. The reversal of 47918509 is 90581974.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 46104100 + 1814409 = 6790^2 + 1347^2 .

It is a cyclic number.

It is not a de Polignac number, because 47918509 - 2³ = 47918501 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (47918501) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 23959254 + 23959255.

It is an arithmetic number, because the mean of its divisors is an integer number (23959255).

Almost surely, 2^47918509 is an apocalyptic number.

It is an amenable number.

47918509 is a deficient number, since it is larger than the sum of its proper divisors (1).

47918509 is an equidigital number, since it uses as much as digits as its factorization.

47918509 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 47918509 is about 6922.3196256746. The cubic root of 47918509 is about 363.2183368266.

The spelling of 47918509 in words is "forty-seven million, nine hundred eighteen thousand, five hundred nine".