47309987 has 4 divisors (see below), whose sum is σ = 47506536. Its totient is φ = 47113440.

The previous prime is 47309971. The next prime is 47309989. The reversal of 47309987 is 78990374.

47309987 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is a semiprime because it is the product of two primes.

It is a cyclic number.

It is not a de Polignac number, because 47309987 - 2⁴ = 47309971 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (47309989) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 97913 + ... + 98394.

It is an arithmetic number, because the mean of its divisors is an integer number (11876634).

Almost surely, 2^47309987 is an apocalyptic number.

47309987 is a deficient number, since it is larger than the sum of its proper divisors (196549).

47309987 is a wasteful number, since it uses less digits than its factorization.

47309987 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 196548.

The product of its (nonzero) digits is 381024, while the sum is 47.

The square root of 47309987 is about 6878.2255705960. The cubic root of 47309987 is about 361.6742666778.

The spelling of 47309987 in words is "forty-seven million, three hundred nine thousand, nine hundred eighty-seven".