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3870 = 232543

3870 has 24 divisors (see below), whose sum is σ = 10296. Its totient is φ = 1008.

The previous prime is 3863. The next prime is 3877. The reversal of 3870 is 783.

It is an interprime number because it is at equal distance from previous prime (3863) and next prime (3877).

It is a Harshad number since it is a multiple of its sum of digits (18).

It is an alternating number because its digits alternate between odd and even.

It is a Curzon number.

It is a congruent number.

It is an inconsummate number, since it does not exist a number n which divided by its sum of digits gives 3870.

It is not an unprimeable number, because it can be changed into a prime (3877) by changing a digit.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 69 + ... + 111.

It is an arithmetic number, because the mean of its divisors is an integer number (429).

3870 is a gapful number since it is divisible by the number (30) formed by its first and last digit.

It is a practical number, because each smaller number is the sum of distinct divisors of 3870, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (5148).

3870 is an abundant number, since it is smaller than the sum of its proper divisors (6426).

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

3870 is a wasteful number, since it uses less digits than its factorization.

3870 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 56 (or 53 counting only the distinct ones).

The product of its (nonzero) digits is 168, while the sum is 18.

The square root of 3870 is about 62.2093240600. The cubic root of 3870 is about 15.7001446969.

The spelling of 3870 in words is "three thousand, eight hundred seventy".

Divisors: 1 2 3 5 6 9 10 15 18 30 43 45 86 90 129 215 258 387 430 645 774 1290 1935 3870