2878640 has 20 divisors (see below), whose sum is σ = 6693024. Its totient is φ = 1151424.

The previous prime is 2878639. The next prime is 2878679. The reversal of 2878640 is 468782.

It is a tau number, because it is divible by the number of its divisors (20).

It is a hoax number, since the sum of its digits (35) coincides with the sum of the digits of its distinct prime factors.

It is a self number, because there is not a number n which added to its sum of digits gives 2878640.

It is an unprimeable number.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 17912 + ... + 18071.

2^2878640 is an apocalyptic number.

2878640 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

2878640 is an abundant number, since it is smaller than the sum of its proper divisors (3814384).

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

2878640 is a wasteful number, since it uses less digits than its factorization.

2878640 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 35996 (or 35990 counting only the distinct ones).

The product of its (nonzero) digits is 21504, while the sum is 35.

The square root of 2878640 is about 1696.6555336897. The cubic root of 2878640 is about 142.2533333994.

The spelling of 2878640 in words is "two million, eight hundred seventy-eight thousand, six hundred forty".