1620849 has 4 divisors (see below), whose sum is σ = 2161136. Its totient is φ = 1080564.

The previous prime is 1620841. The next prime is 1620881. The reversal of 1620849 is 9480261.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4.

It is not a de Polignac number, because 1620849 - 2³ = 1620841 is a prime.

It is an Ulam number.

It is a D-number.

It is a Duffinian number.

It is a Curzon number.

1620849 is a lucky number.

It is not an unprimeable number, because it can be changed into a prime (1620841) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 270139 + ... + 270144.

It is an arithmetic number, because the mean of its divisors is an integer number (540284).

2^1620849 is an apocalyptic number.

It is an amenable number.

1620849 is a deficient number, since it is larger than the sum of its proper divisors (540287).

1620849 is an equidigital number, since it uses as much as digits as its factorization.

1620849 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 540286.

The product of its (nonzero) digits is 3456, while the sum is 30.

The square root of 1620849 is about 1273.1256811486. The cubic root of 1620849 is about 117.4665424583.

The spelling of 1620849 in words is "one million, six hundred twenty thousand, eight hundred forty-nine".