47878813 has 2 divisors, whose sum is σ = 47878814. Its totient is φ = 47878812.

The previous prime is 47878811. The next prime is 47878867. The reversal of 47878813 is 31887874.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 45454564 + 2424249 = 6742^2 + 1557^2 .

It is a cyclic number.

It is not a de Polignac number, because 47878813 - 2¹ = 47878811 is a prime.

Together with 47878811, it forms a pair of twin primes.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (47878811) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 23939406 + 23939407.

It is an arithmetic number, because the mean of its divisors is an integer number (23939407).

Almost surely, 2^47878813 is an apocalyptic number.

It is an amenable number.

47878813 is a deficient number, since it is larger than the sum of its proper divisors (1).

47878813 is an equidigital number, since it uses as much as digits as its factorization.

47878813 is an evil number, because the sum of its binary digits is even.

The product of its digits is 301056, while the sum is 46.

The square root of 47878813 is about 6919.4517846431. The cubic root of 47878813 is about 363.1180116520.

The spelling of 47878813 in words is "forty-seven million, eight hundred seventy-eight thousand, eight hundred thirteen".