2639868 has 48 divisors (see below), whose sum is σ = 7682304. Its totient is φ = 685440.

The previous prime is 2639863. The next prime is 2639869. The reversal of 2639868 is 8689362.

It is a Harshad number since it is a multiple of its sum of digits (42).

It is a d-powerful number, because it can be written as 2²¹ + 6⁴ + 3⁷ + 9⁶ + 8 + 6⁵ + 8 .

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (2639863) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 505 + ... + 2352.

It is an arithmetic number, because the mean of its divisors is an integer number (160048).

2^2639868 is an apocalyptic number.

2639868 is a gapful number since it is divisible by the number (28) formed by its first and last digit.

It is an amenable number.

2639868 is an abundant number, since it is smaller than the sum of its proper divisors (5042436).

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

2639868 is a wasteful number, since it uses less digits than its factorization.

2639868 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2882 (or 2880 counting only the distinct ones).

The product of its digits is 124416, while the sum is 42.

The square root of 2639868 is about 1624.7670602274. The cubic root of 2639868 is about 138.2061610874.

The spelling of 2639868 in words is "two million, six hundred thirty-nine thousand, eight hundred sixty-eight".