3977820 has 216 divisors, whose sum is σ = 15685488. Its totient is φ = 806400.

The previous prime is 3977819. The next prime is 3977849. The reversal of 3977820 is 287793.

It is a Smith number, since the sum of its digits (36) coincides with the sum of the digits of its prime factors.

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 71 ways as a sum of consecutive naturals, for example, 97000 + ... + 97040.

It is an arithmetic number, because the mean of its divisors is an integer number (72618).

Almost surely, 2^3977820 is an apocalyptic number.

3977820 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 3977820, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (7842744).

3977820 is an abundant number, since it is smaller than the sum of its proper divisors (11707668).

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

3977820 is a wasteful number, since it uses less digits than its factorization.

3977820 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 81 (or 69 counting only the distinct ones).

The product of its (nonzero) digits is 21168, while the sum is 36.

The square root of 3977820 is about 1994.4472918581. The cubic root of 3977820 is about 158.4461565827.

The spelling of 3977820 in words is "three million, nine hundred seventy-seven thousand, eight hundred twenty".