2778946 has 4 divisors (see below), whose sum is σ = 4168422. Its totient is φ = 1389472.

The previous prime is 2778917. The next prime is 2778967. The reversal of 2778946 is 6498772.

It is a semiprime because it is the product of two primes.

It can be written as a sum of positive squares in only one way, i.e., 2436721 + 342225 = 1561^2 + 585^2 .

It is an unprimeable number.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 694735 + ... + 694738.

2^2778946 is an apocalyptic number.

2778946 is a deficient number, since it is larger than the sum of its proper divisors (1389476).

2778946 is a wasteful number, since it uses less digits than its factorization.

2778946 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1389475.

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

The square root of 2778946 is about 1667.0170964930. The cubic root of 2778946 is about 140.5918144574.

Subtracting from 2778946 its sum of digits (43), we obtain a triangular number (2778903 = T₂₃₅₇).

The spelling of 2778946 in words is "two million, seven hundred seventy-eight thousand, nine hundred forty-six".