1720020 has 48 divisors (see below), whose sum is σ = 4878720. Its totient is φ = 452736.

The previous prime is 1720003. The next prime is 1720031. The reversal of 1720020 is 200271.

It is a Harshad number since it is a multiple of its sum of digits (12).

It is a junction number, because it is equal to n+sod(n) for n = 1719978 and 1720005.

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, 6409 + ... + 6671.

It is an arithmetic number, because the mean of its divisors is an integer number (101640).

2^1720020 is an apocalyptic number.

1720020 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 1720020, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (2439360).

1720020 is an abundant number, since it is smaller than the sum of its proper divisors (3158700).

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

1720020 is a wasteful number, since it uses less digits than its factorization.

1720020 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 384 (or 382 counting only the distinct ones).

The product of its (nonzero) digits is 28, while the sum is 12.

The square root of 1720020 is about 1311.4953297668. The cubic root of 1720020 is about 119.8149926935.

Adding to 1720020 its reverse (200271), we get a palindrome (1920291).

The spelling of 1720020 in words is "one million, seven hundred twenty thousand, twenty".