2778649923 has 16 divisors (see below), whose sum is σ = 4241060096. Its totient is φ = 1585202400.

The previous prime is 2778649919. The next prime is 2778649931. The reversal of 2778649923 is 3299468772.

It is not a de Polignac number, because 2778649923 - 2² = 2778649919 is a prime.

It is not an unprimeable number, because it can be changed into a prime (2778649943) 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 in 15 ways as a sum of consecutive naturals, for example, 95053 + ... + 120798.

It is an arithmetic number, because the mean of its divisors is an integer number (265066256).

Almost surely, 2^2778649923 is an apocalyptic number.

2778649923 is a deficient number, since it is larger than the sum of its proper divisors (1462410173).

2778649923 is a wasteful number, since it uses less digits than its factorization.

2778649923 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 216474.

The product of its digits is 9144576, while the sum is 57.

The square root of 2778649923 is about 52712.9009161894. The cubic root of 2778649923 is about 1405.8682125957.

The spelling of 2778649923 in words is "two billion, seven hundred seventy-eight million, six hundred forty-nine thousand, nine hundred twenty-three".