2778731047 has 4 divisors (see below), whose sum is σ = 2817868176. Its totient is φ = 2739593920.

The previous prime is 2778731029. The next prime is 2778731051. The reversal of 2778731047 is 7401378772.

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 2778731047 - 2⁷ = 2778730919 is a prime.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 2778730988 and 2778731006.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (2778731027) 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, 19568458 + ... + 19568599.

It is an arithmetic number, because the mean of its divisors is an integer number (704467044).

Almost surely, 2^2778731047 is an apocalyptic number.

2778731047 is a deficient number, since it is larger than the sum of its proper divisors (39137129).

2778731047 is an equidigital number, since it uses as much as digits as its factorization.

2778731047 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 39137128.

The product of its (nonzero) digits is 460992, while the sum is 46.

The square root of 2778731047 is about 52713.6703996221. The cubic root of 2778731047 is about 1405.8818941252.

The spelling of 2778731047 in words is "two billion, seven hundred seventy-eight million, seven hundred thirty-one thousand, forty-seven".