1620220 has 48 divisors (see below), whose sum is σ = 3967488. Its totient is φ = 544320.

The previous prime is 1620217. The next prime is 1620233. The reversal of 1620220 is 220261.

It is a happy number.

It is a super-2 number, since 2×1620220² = 5250225696800, which contains 22 as substring.

It is a self number, because there is not a number n which added to its sum of digits gives 1620220.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 9859 + ... + 10021.

It is an arithmetic number, because the mean of its divisors is an integer number (82656).

2^1620220 is an apocalyptic number.

1620220 is a gapful number since it is divisible by the number (10) 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 1620220, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (1983744).

1620220 is an abundant number, since it is smaller than the sum of its proper divisors (2347268).

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

1620220 is a wasteful number, since it uses less digits than its factorization.

1620220 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 250 (or 248 counting only the distinct ones).

The product of its (nonzero) digits is 48, while the sum is 13.

The square root of 1620220 is about 1272.8786273640. The cubic root of 1620220 is about 117.4513454813.

Adding to 1620220 its reverse (220261), we get a palindrome (1840481).

The spelling of 1620220 in words is "one million, six hundred twenty thousand, two hundred twenty".