7861820 has 48 divisors (see below), whose sum is σ = 18416160. Its totient is φ = 2801664.

The previous prime is 7861811. The next prime is 7861823. The reversal of 7861820 is 281687.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (7861823) 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, 5852 + ... + 7068.

It is an arithmetic number, because the mean of its divisors is an integer number (383670).

Almost surely, 2^7861820 is an apocalyptic number.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 7861820, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (9208080).

7861820 is an abundant number, since it is smaller than the sum of its proper divisors (10554340).

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

7861820 is a wasteful number, since it uses less digits than its factorization.

7861820 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1262 (or 1260 counting only the distinct ones).

The product of its (nonzero) digits is 5376, while the sum is 32.

The square root of 7861820 is about 2803.8937212384. The cubic root of 7861820 is about 198.8418058787.

The spelling of 7861820 in words is "seven million, eight hundred sixty-one thousand, eight hundred twenty".