1628820 has 36 divisors (see below), whose sum is σ = 4941300. Its totient is φ = 434304.

The previous prime is 1628801. The next prime is 1628839. The reversal of 1628820 is 288261.

It is an interprime number because it is at equal distance from previous prime (1628801) and next prime (1628839).

It can be written as a sum of positive squares in 2 ways, for example, as 992016 + 636804 = 996^2 + 798^2 .

It is a tau number, because it is divible by the number of its divisors (36).

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 4345 + ... + 4704.

2^1628820 is an apocalyptic number.

1628820 is a gapful number since it is divisible by the number (10) formed by its first and last digit.

It is an amenable number.

1628820 is an abundant number, since it is smaller than the sum of its proper divisors (3312480).

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

1628820 is a wasteful number, since it uses less digits than its factorization.

1628820 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 9064 (or 9059 counting only the distinct ones).

The product of its (nonzero) digits is 1536, while the sum is 27.

The square root of 1628820 is about 1276.2523261487. The cubic root of 1628820 is about 117.6587863799.

The spelling of 1628820 in words is "one million, six hundred twenty-eight thousand, eight hundred twenty".