1620520 has 64 divisors (see below), whose sum is σ = 4147200. Its totient is φ = 564480.

The previous prime is 1620517. The next prime is 1620523. The reversal of 1620520 is 250261.

It is a happy number.

It is an interprime number because it is at equal distance from previous prime (1620517) and next prime (1620523).

It is a junction number, because it is equal to n+sod(n) for n = 1620494 and 1620503.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1620523) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 12697 + ... + 12823.

It is an arithmetic number, because the mean of its divisors is an integer number (64800).

2^1620520 is an apocalyptic number.

1620520 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 1620520, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (2073600).

1620520 is an abundant number, since it is smaller than the sum of its proper divisors (2526680).

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

1620520 is a wasteful number, since it uses less digits than its factorization.

1620520 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 178 (or 174 counting only the distinct ones).

The product of its (nonzero) digits is 120, while the sum is 16.

The square root of 1620520 is about 1272.9964650383. The cubic root of 1620520 is about 117.4585941326.

Adding to 1620520 its reverse (250261), we get a palindrome (1870781).

The spelling of 1620520 in words is "one million, six hundred twenty thousand, five hundred twenty".