2681640 has 128 divisors (see below), whose sum is σ = 9676800. Its totient is φ = 656640.

The previous prime is 2681617. The next prime is 2681663. The reversal of 2681640 is 461862.

It is an interprime number because it is at equal distance from previous prime (2681617) and next prime (2681663).

It is a Harshad number since it is a multiple of its sum of digits (27).

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 13945 + ... + 14135.

It is an arithmetic number, because the mean of its divisors is an integer number (75600).

2^2681640 is an apocalyptic number.

2681640 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 2681640, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (4838400).

2681640 is an abundant number, since it is smaller than the sum of its proper divisors (6995160).

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

2681640 is a wasteful number, since it uses less digits than its factorization.

2681640 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 224 (or 214 counting only the distinct ones).

The product of its (nonzero) digits is 2304, while the sum is 27.

The square root of 2681640 is about 1637.5713724904. The cubic root of 2681640 is about 138.9313188291.

It can be divided in two parts, 2681 and 640, that added together give a triangular number (3321 = T₈₁).

The spelling of 2681640 in words is "two million, six hundred eighty-one thousand, six hundred forty".