1620205 has 8 divisors (see below), whose sum is σ = 1953504. Its totient is φ = 1290000.

The previous prime is 1620161. The next prime is 1620209. The reversal of 1620205 is 5020261.

It is a happy number.

It is a sphenic number, since it is the product of 3 distinct primes.

It is a de Polignac number, because none of the positive numbers 2^k-1620205 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1620209) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 610 + ... + 1900.

It is an arithmetic number, because the mean of its divisors is an integer number (244188).

2^1620205 is an apocalyptic number.

It is an amenable number.

1620205 is a deficient number, since it is larger than the sum of its proper divisors (333299).

1620205 is a wasteful number, since it uses less digits than its factorization.

1620205 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1547.

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

The square root of 1620205 is about 1272.8727351939. The cubic root of 1620205 is about 117.4509830253.

Adding to 1620205 its reverse (5020261), we get a palindrome (6640466).

The spelling of 1620205 in words is "one million, six hundred twenty thousand, two hundred five".