1620618916 has 72 divisors (see below), whose sum is σ = 3465189504. Its totient is φ = 648426240.

The previous prime is 1620618911. The next prime is 1620618971. The reversal of 1620618916 is 6198160261.

It is not an unprimeable number, because it can be changed into a prime (1620618911) by changing a digit.

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 23 ways as a sum of consecutive naturals, for example, 1190076 + ... + 1191436.

It is an arithmetic number, because the mean of its divisors is an integer number (48127632).

Almost surely, 2^1620618916 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 1620618916, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (1732594752).

1620618916 is an abundant number, since it is smaller than the sum of its proper divisors (1844570588).

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

1620618916 is a wasteful number, since it uses less digits than its factorization.

1620618916 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1481 (or 1436 counting only the distinct ones).

The product of its (nonzero) digits is 31104, while the sum is 40.

The square root of 1620618916 is about 40256.9114066144. The cubic root of 1620618916 is about 1174.6098396175.

The spelling of 1620618916 in words is "one billion, six hundred twenty million, six hundred eighteen thousand, nine hundred sixteen".