2775640 has 64 divisors (see below), whose sum is σ = 7464960. Its totient is φ = 908160.

The previous prime is 2775637. The next prime is 2775649. The reversal of 2775640 is 465772.

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

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (2775649) 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, 6225 + ... + 6655.

It is an arithmetic number, because the mean of its divisors is an integer number (116640).

2^2775640 is an apocalyptic number.

2775640 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 2775640, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (3732480).

2775640 is an abundant number, since it is smaller than the sum of its proper divisors (4689320).

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

2775640 is a wasteful number, since it uses less digits than its factorization.

2775640 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 472 (or 468 counting only the distinct ones).

The product of its (nonzero) digits is 11760, while the sum is 31.

The square root of 2775640 is about 1666.0252098933. The cubic root of 2775640 is about 140.5360401965.

The spelling of 2775640 in words is "two million, seven hundred seventy-five thousand, six hundred forty".