1021608640 has 112 divisors (see below), whose sum is σ = 2633289120. Its totient is φ = 375275520.

The previous prime is 1021608631. The next prime is 1021608671. The reversal of 1021608640 is 468061201.

It is a junction number, because it is equal to n+sod(n) for n = 1021608599 and 1021608608.

It is an unprimeable number.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 1002051 + ... + 1003069.

It is an arithmetic number, because the mean of its divisors is an integer number (23511510).

Almost surely, 2^1021608640 is an apocalyptic number.

1021608640 is a gapful number since it is divisible by the number (10) 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 1021608640, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (1316644560).

1021608640 is an abundant number, since it is smaller than the sum of its proper divisors (1611680480).

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

1021608640 is a wasteful number, since it uses less digits than its factorization.

1021608640 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1290 (or 1280 counting only the distinct ones).

The product of its (nonzero) digits is 2304, while the sum is 28.

The square root of 1021608640 is about 31962.6131597528. The cubic root of 1021608640 is about 1007.1516125140.

Adding to 1021608640 its reverse (468061201), we get a palindrome (1489669841).

The spelling of 1021608640 in words is "one billion, twenty-one million, six hundred eight thousand, six hundred forty".