47784139 has 4 divisors (see below), whose sum is σ = 51459856. Its totient is φ = 44108424.

The previous prime is 47784119. The next prime is 47784173. The reversal of 47784139 is 93148774.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 93148774 = 2 ⋅46574387.

It is a cyclic number.

It is not a de Polignac number, because 47784139 - 2¹⁹ = 47259851 is a prime.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 47784095 and 47784104.

It is not an unprimeable number, because it can be changed into a prime (47784109) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 1837839 + ... + 1837864.

It is an arithmetic number, because the mean of its divisors is an integer number (12864964).

Almost surely, 2^47784139 is an apocalyptic number.

47784139 is a deficient number, since it is larger than the sum of its proper divisors (3675717).

47784139 is a wasteful number, since it uses less digits than its factorization.

47784139 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 3675716.

The product of its digits is 169344, while the sum is 43.

The square root of 47784139 is about 6912.6072505242. The cubic root of 47784139 is about 362.8785144952.

The spelling of 47784139 in words is "forty-seven million, seven hundred eighty-four thousand, one hundred thirty-nine".