1621106604 has 144 divisors (see below), whose sum is σ = 4799759328. Its totient is φ = 456689664.

The previous prime is 1621106573. The next prime is 1621106651. The reversal of 1621106604 is 4066011261.

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 47 ways as a sum of consecutive naturals, for example, 291619 + ... + 297125.

It is an arithmetic number, because the mean of its divisors is an integer number (33331662).

Almost surely, 2^1621106604 is an apocalyptic number.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 1621106604, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (2399879664).

1621106604 is an abundant number, since it is smaller than the sum of its proper divisors (3178652724).

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

1621106604 is a wasteful number, since it uses less digits than its factorization.

1621106604 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 5584 (or 5579 counting only the distinct ones).

The product of its (nonzero) digits is 1728, while the sum is 27.

The square root of 1621106604 is about 40262.9681469213. The cubic root of 1621106604 is about 1174.7276517419.

Adding to 1621106604 its reverse (4066011261), we get a palindrome (5687117865).

The spelling of 1621106604 in words is "one billion, six hundred twenty-one million, one hundred six thousand, six hundred four".