3866820 has 72 divisors (see below), whose sum is σ = 11553024. Its totient is φ = 966144.

The previous prime is 3866809. The next prime is 3866839. The reversal of 3866820 is 286683.

It is an unprimeable number.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 17229 + ... + 17451.

Almost surely, 2^3866820 is an apocalyptic number.

3866820 is a gapful number since it is divisible by the number (30) 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 3866820, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (5776512).

3866820 is an abundant number, since it is smaller than the sum of its proper divisors (7686204).

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

3866820 is a wasteful number, since it uses less digits than its factorization.

3866820 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 269 (or 250 counting only the distinct ones).

The product of its (nonzero) digits is 13824, while the sum is 33.

The square root of 3866820 is about 1966.4231487653. The cubic root of 3866820 is about 156.9584322047.

The spelling of 3866820 in words is "three million, eight hundred sixty-six thousand, eight hundred twenty".