2491778 has 8 divisors (see below), whose sum is σ = 3749772. Its totient is φ = 1241856.

The previous prime is 2491777. The next prime is 2491787. The reversal of 2491778 is 8771942.

It can be written as a sum of positive squares in 2 ways, for example, as 2181529 + 310249 = 1477^2 + 557^2 .

It is a sphenic number, since it is the product of 3 distinct primes.

It is not an unprimeable number, because it can be changed into a prime (2491777) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (7) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 1175 + ... + 2522.

2^2491778 is an apocalyptic number.

2491778 is a deficient number, since it is larger than the sum of its proper divisors (1257994).

2491778 is a wasteful number, since it uses less digits than its factorization.

2491778 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 4036.

The product of its digits is 28224, while the sum is 38.

The square root of 2491778 is about 1578.5366641292. The cubic root of 2491778 is about 135.5719311440.

The spelling of 2491778 in words is "two million, four hundred ninety-one thousand, seven hundred seventy-eight".