4121820 has 96 divisors (see below), whose sum is σ = 13608000. Its totient is φ = 1032192.

The previous prime is 4121809. The next prime is 4121827. The reversal of 4121820 is 281214.

It is a super-2 number, since 2×4121820² = 33978800224800, which contains 22 as substring.

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

It is a junction number, because it is equal to n+sod(n) for n = 4121793 and 4121802.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (4121827) by changing a digit.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 8956 + ... + 9404.

It is an arithmetic number, because the mean of its divisors is an integer number (141750).

Almost surely, 2^4121820 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 4121820, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (6804000).

4121820 is an abundant number, since it is smaller than the sum of its proper divisors (9486180).

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

4121820 is a wasteful number, since it uses less digits than its factorization.

4121820 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 484 (or 476 counting only the distinct ones).

The product of its (nonzero) digits is 128, while the sum is 18.

The square root of 4121820 is about 2030.2265883393. The cubic root of 4121820 is about 160.3354939488.

Subtracting from 4121820 its reverse (281214), we obtain a triangular number (3840606 = T₂₇₇₁).

The spelling of 4121820 in words is "four million, one hundred twenty-one thousand, eight hundred twenty".