1620290 has 32 divisors (see below), whose sum is σ = 3386880. Its totient is φ = 546624.

The previous prime is 1620271. The next prime is 1620319. The reversal of 1620290 is 920261.

It is a Curzon number.

It is an unprimeable number.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 5384 + ... + 5676.

It is an arithmetic number, because the mean of its divisors is an integer number (105840).

2^1620290 is an apocalyptic number.

1620290 is a gapful number since it is divisible by the number (10) formed by its first and last digit.

1620290 is an abundant number, since it is smaller than the sum of its proper divisors (1766590).

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

1620290 is a wasteful number, since it uses less digits than its factorization.

1620290 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 386.

The product of its (nonzero) digits is 216, while the sum is 20.

The square root of 1620290 is about 1272.9061237970. The cubic root of 1620290 is about 117.4530369133.

The spelling of 1620290 in words is "one million, six hundred twenty thousand, two hundred ninety".