47517721 has 2 divisors, whose sum is σ = 47517722. Its totient is φ = 47517720.

The previous prime is 47517707. The next prime is 47517791. The reversal of 47517721 is 12771574.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 47114496 + 403225 = 6864^2 + 635^2 .

It is a cyclic number.

It is not a de Polignac number, because 47517721 - 2⁷ = 47517593 is a prime.

It is not a weakly prime, because it can be changed into another prime (47517791) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 23758860 + 23758861.

It is an arithmetic number, because the mean of its divisors is an integer number (23758861).

Almost surely, 2^47517721 is an apocalyptic number.

It is an amenable number.

47517721 is a deficient number, since it is larger than the sum of its proper divisors (1).

47517721 is an equidigital number, since it uses as much as digits as its factorization.

47517721 is an evil number, because the sum of its binary digits is even.

The product of its digits is 13720, while the sum is 34.

The square root of 47517721 is about 6893.3098726229. The cubic root of 47517721 is about 362.2028537568.

The spelling of 47517721 in words is "forty-seven million, five hundred seventeen thousand, seven hundred twenty-one".