2011723778 has 4 divisors (see below), whose sum is σ = 3017585670. Its totient is φ = 1005861888.

The previous prime is 2011723733. The next prime is 2011723793. The reversal of 2011723778 is 8773271102.

It is a happy number.

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., 1391066209 + 620657569 = 37297^2 + 24913^2 .

It is a Curzon number.

It is an unprimeable number.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 502930943 + ... + 502930946.

Almost surely, 2^2011723778 is an apocalyptic number.

2011723778 is a deficient number, since it is larger than the sum of its proper divisors (1005861892).

2011723778 is a wasteful number, since it uses less digits than its factorization.

2011723778 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1005861891.

The product of its (nonzero) digits is 32928, while the sum is 38.

The square root of 2011723778 is about 44852.2438457654. The cubic root of 2011723778 is about 1262.3780942712.

The spelling of 2011723778 in words is "two billion, eleven million, seven hundred twenty-three thousand, seven hundred seventy-eight".