2787904 has 56 divisors (see below), whose sum is σ = 6502400. Its totient is φ = 1185408.

The previous prime is 2787859. The next prime is 2787907. The reversal of 2787904 is 4097872.

It is a happy number.

It is a tau number, because it is divible by the number of its divisors (56).

It is an Ulam number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (2787907) 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 7 ways as a sum of consecutive naturals, for example, 21889 + ... + 22015.

2^2787904 is an apocalyptic number.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 2787904, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (3251200).

2787904 is an abundant number, since it is smaller than the sum of its proper divisors (3714496).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

2787904 is an equidigital number, since it uses as much as digits as its factorization.

2787904 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 160 (or 136 counting only the distinct ones).

The product of its (nonzero) digits is 28224, while the sum is 37.

The square root of 2787904 is about 1669.7017697781. The cubic root of 2787904 is about 140.7427194688.

The spelling of 2787904 in words is "two million, seven hundred eighty-seven thousand, nine hundred four".