47087721 has 12 divisors (see below), whose sum is σ = 69675060. Its totient is φ = 30625920.

The previous prime is 47087707. The next prime is 47087743. The reversal of 47087721 is 12778074.

It can be written as a sum of positive squares in 2 ways, for example, as 1929321 + 45158400 = 1389^2 + 6720^2 .

It is not a de Polignac number, because 47087721 - 2¹¹ = 47085673 is a prime.

It is a Smith number, since the sum of its digits (36) coincides with the sum of the digits of its prime factors.

It is not an unprimeable number, because it can be changed into a prime (47087771) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 63436 + ... + 64173.

It is an arithmetic number, because the mean of its divisors is an integer number (5806255).

Almost surely, 2^47087721 is an apocalyptic number.

47087721 is a gapful number since it is divisible by the number (41) formed by its first and last digit.

It is an amenable number.

47087721 is a deficient number, since it is larger than the sum of its proper divisors (22587339).

47087721 is a wasteful number, since it uses less digits than its factorization.

47087721 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 127656 (or 127653 counting only the distinct ones).

The product of its (nonzero) digits is 21952, while the sum is 36.

The square root of 47087721 is about 6862.0493294642. The cubic root of 47087721 is about 361.1069860901.

The spelling of 47087721 in words is "forty-seven million, eighty-seven thousand, seven hundred twenty-one".