1002006640 has 80 divisors (see below), whose sum is σ = 2399810688. Its totient is φ = 388862208.

The previous prime is 1002006623. The next prime is 1002006653. The reversal of 1002006640 is 466002001.

It is a tau number, because it is divible by the number of its divisors (80).

It is a congruent number.

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, 559827 + ... + 561613.

Almost surely, 2^1002006640 is an apocalyptic number.

1002006640 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 1002006640, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (1199905344).

1002006640 is an abundant number, since it is smaller than the sum of its proper divisors (1397804048).

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

1002006640 is a wasteful number, since it uses less digits than its factorization.

1002006640 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2006 (or 2000 counting only the distinct ones).

The product of its (nonzero) digits is 288, while the sum is 19.

The square root of 1002006640 is about 31654.4884653030. The cubic root of 1002006640 is about 1000.6684330976.

Adding to 1002006640 its reverse (466002001), we get a palindrome (1468008641).

The spelling of 1002006640 in words is "one billion, two million, six thousand, six hundred forty".