1620983808 has 90 divisors (see below), whose sum is σ = 4683125174. Its totient is φ = 540278784.

The previous prime is 1620983783. The next prime is 1620983809. The reversal of 1620983808 is 8083890261.

It can be written as a sum of positive squares in only one way, i.e., 1141899264 + 479084544 = 33792^2 + 21888^2 .

It is not an unprimeable number, because it can be changed into a prime (1620983809) by changing a digit.

It is a polite number, since it can be written in 5 ways as a sum of consecutive naturals, for example, 141960 + ... + 152952.

Almost surely, 2^1620983808 is an apocalyptic number.

1620983808 is a gapful number since it is divisible by the number (18) formed by its first and last digit.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 1620983808, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (2341562587).

1620983808 is an abundant number, since it is smaller than the sum of its proper divisors (3062141366).

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

1620983808 is an equidigital number, since it uses as much as digits as its factorization.

1620983808 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 11027 (or 10998 counting only the distinct ones).

The product of its (nonzero) digits is 165888, while the sum is 45.

The square root of 1620983808 is about 40261.4431932091. The cubic root of 1620983808 is about 1174.6979898021.

The spelling of 1620983808 in words is "one billion, six hundred twenty million, nine hundred eighty-three thousand, eight hundred eight".