1620245 has 16 divisors (see below), whose sum is σ = 2151360. Its totient is φ = 1161600.

The previous prime is 1620239. The next prime is 1620247. The reversal of 1620245 is 5420261.

It is a happy number.

It is a de Polignac number, because none of the positive numbers 2^k-1620245 is a prime.

It is a Curzon number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1620247) 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, 4730 + ... + 5060.

It is an arithmetic number, because the mean of its divisors is an integer number (134460).

2^1620245 is an apocalyptic number.

It is an amenable number.

1620245 is a deficient number, since it is larger than the sum of its proper divisors (531115).

1620245 is a wasteful number, since it uses less digits than its factorization.

1620245 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 436.

The product of its (nonzero) digits is 480, while the sum is 20.

The square root of 1620245 is about 1272.8884475868. Note that the first 3 decimals coincide. The cubic root of 1620245 is about 117.4519495698.

It can be divided in two parts, 1620 and 245, that multiplied together give a square (396900 = 630²).

The spelling of 1620245 in words is "one million, six hundred twenty thousand, two hundred forty-five".