1620648 has 80 divisors (see below), whose sum is σ = 4726260. Its totient is φ = 518400.

The previous prime is 1620631. The next prime is 1620667. The reversal of 1620648 is 8460261.

1620648 is a `hidden beast` number, since 16 + 2 + 0 + 648 = 666.

It can be written as a sum of positive squares in 2 ways, for example, as 1127844 + 492804 = 1062^2 + 702^2 .

It is a Harshad number since it is a multiple of its sum of digits (27).

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 19 ways as a sum of consecutive naturals, for example, 26538 + ... + 26598.

2^1620648 is an apocalyptic number.

1620648 is a gapful number since it is divisible by the number (18) 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 1620648, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (2363130).

1620648 is an abundant number, since it is smaller than the sum of its proper divisors (3105612).

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

1620648 is a wasteful number, since it uses less digits than its factorization.

1620648 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 120 (or 107 counting only the distinct ones).

The product of its (nonzero) digits is 2304, while the sum is 27.

The square root of 1620648 is about 1273.0467391263. The cubic root of 1620648 is about 117.4616866182.

The spelling of 1620648 in words is "one million, six hundred twenty thousand, six hundred forty-eight".