1620521606 has 16 divisors (see below), whose sum is σ = 2665230480. Its totient is φ = 732859680.

The previous prime is 1620521593. The next prime is 1620521611. The reversal of 1620521606 is 6061250261.

It is a Curzon number.

It is a congruent number.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 182621 + ... + 191288.

It is an arithmetic number, because the mean of its divisors is an integer number (166576905).

Almost surely, 2^1620521606 is an apocalyptic number.

1620521606 is a deficient number, since it is larger than the sum of its proper divisors (1044708874).

1620521606 is a wasteful number, since it uses less digits than its factorization.

1620521606 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 374119.

The product of its (nonzero) digits is 4320, while the sum is 29.

The square root of 1620521606 is about 40255.7027761285. The cubic root of 1620521606 is about 1174.5863293462.

Adding to 1620521606 its reverse (6061250261), we get a palindrome (7681771867).

The spelling of 1620521606 in words is "one billion, six hundred twenty million, five hundred twenty-one thousand, six hundred six".