1620365 has 4 divisors (see below), whose sum is σ = 1944444. Its totient is φ = 1296288.

The previous prime is 1620347. The next prime is 1620371. The reversal of 1620365 is 5630261.

It is a semiprime because it is the product of two primes.

It can be written as a sum of positive squares in 2 ways, for example, as 175561 + 1444804 = 419^2 + 1202^2 .

It is a cyclic number.

It is not a de Polignac number, because 1620365 - 2¹⁰ = 1619341 is a prime.

It is a Duffinian number.

It is a self number, because there is not a number n which added to its sum of digits gives 1620365.

It is a congruent number.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 162032 + ... + 162041.

It is an arithmetic number, because the mean of its divisors is an integer number (486111).

2^1620365 is an apocalyptic number.

It is an amenable number.

1620365 is a deficient number, since it is larger than the sum of its proper divisors (324079).

1620365 is an equidigital number, since it uses as much as digits as its factorization.

1620365 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 324078.

The product of its (nonzero) digits is 1080, while the sum is 23.

The square root of 1620365 is about 1272.9355836019. The cubic root of 1620365 is about 117.4548491078.

The spelling of 1620365 in words is "one million, six hundred twenty thousand, three hundred sixty-five".