3869820 has 36 divisors (see below), whose sum is σ = 11739000. Its totient is φ = 1031904.

The previous prime is 3869807. The next prime is 3869849. The reversal of 3869820 is 289683.

It is a tau number, because it is divible by the number of its divisors (36).

It is a Harshad number since it is a multiple of its sum of digits (36).

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 10570 + ... + 10929.

Almost surely, 2^3869820 is an apocalyptic number.

3869820 is a gapful number since it is divisible by the number (30) formed by its first and last digit.

It is an amenable number.

3869820 is an abundant number, since it is smaller than the sum of its proper divisors (7869180).

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

3869820 is a wasteful number, since it uses less digits than its factorization.

3869820 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 21514 (or 21509 counting only the distinct ones).

The product of its (nonzero) digits is 20736, while the sum is 36.

The square root of 3869820 is about 1967.1858071875. The cubic root of 3869820 is about 156.9990128003. Note that the first 3 decimals are identical.

The spelling of 3869820 in words is "three million, eight hundred sixty-nine thousand, eight hundred twenty".