47639987 has 2 divisors, whose sum is σ = 47639988. Its totient is φ = 47639986.

The previous prime is 47639981. The next prime is 47639989. The reversal of 47639987 is 78993674.

It is a strong prime.

It is a cyclic number.

It is not a de Polignac number, because 47639987 - 2⁴ = 47639971 is a prime.

It is a super-2 number, since 2×47639987² = 4539136722720338, which contains 22 as substring.

Together with 47639989, it forms a pair of twin primes.

It is a Chen prime.

It is not a weakly prime, because it can be changed into another prime (47639981) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 23819993 + 23819994.

It is an arithmetic number, because the mean of its divisors is an integer number (23819994).

Almost surely, 2^47639987 is an apocalyptic number.

47639987 is a deficient number, since it is larger than the sum of its proper divisors (1).

47639987 is an equidigital number, since it uses as much as digits as its factorization.

47639987 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 2286144, while the sum is 53.

The square root of 47639987 is about 6902.1726289626. The cubic root of 47639987 is about 362.5132443833.

The spelling of 47639987 in words is "forty-seven million, six hundred thirty-nine thousand, nine hundred eighty-seven".