2051878 has 4 divisors (see below), whose sum is σ = 3077820. Its totient is φ = 1025938.

The previous prime is 2051851. The next prime is 2051887. The reversal of 2051878 is 8781502.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 8781502 = 2 ⋅4390751.

It is a Smith number, since the sum of its digits (31) coincides with the sum of the digits of its prime factors. Since it is squarefree, it is also a hoax number.

It is a congruent number.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 512968 + ... + 512971.

It is an arithmetic number, because the mean of its divisors is an integer number (769455).

2^2051878 is an apocalyptic number.

2051878 is a deficient number, since it is larger than the sum of its proper divisors (1025942).

2051878 is a wasteful number, since it uses less digits than its factorization.

2051878 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1025941.

The product of its (nonzero) digits is 4480, while the sum is 31.

The square root of 2051878 is about 1432.4377822440. The cubic root of 2051878 is about 127.0721891031.

The spelling of 2051878 in words is "two million, fifty-one thousand, eight hundred seventy-eight".