1620486784 has 128 divisors (see below), whose sum is σ = 3934033920. Its totient is φ = 649052160.

The previous prime is 1620486779. The next prime is 1620486787. The reversal of 1620486784 is 4876840261.

It is a tau number, because it is divible by the number of its divisors (128).

It is not an unprimeable number, because it can be changed into a prime (1620486787) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 2909034 + ... + 2909590.

It is an arithmetic number, because the mean of its divisors is an integer number (30734640).

Almost surely, 2^1620486784 is an apocalyptic number.

1620486784 is a gapful number since it is divisible by the number (14) 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 1620486784, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (1967016960).

1620486784 is an abundant number, since it is smaller than the sum of its proper divisors (2313547136).

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

1620486784 is a wasteful number, since it uses less digits than its factorization.

1620486784 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 786 (or 774 counting only the distinct ones).

The product of its (nonzero) digits is 516096, while the sum is 46.

The square root of 1620486784 is about 40255.2702636562. The cubic root of 1620486784 is about 1174.5779160596.

The spelling of 1620486784 in words is "one billion, six hundred twenty million, four hundred eighty-six thousand, seven hundred eighty-four".