6985894640 has 80 divisors (see below), whose sum is σ = 16894918656. Its totient is φ = 2683449600.

The previous prime is 6985894613. The next prime is 6985894661. The reversal of 6985894640 is 464985896.

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

It is a self number, because there is not a number n which added to its sum of digits gives 6985894640.

It is a congruent number.

It is an unprimeable number.

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 15 ways as a sum of consecutive naturals, for example, 314129 + ... + 335631.

Almost surely, 2^6985894640 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 6985894640, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (8447459328).

6985894640 is an abundant number, since it is smaller than the sum of its proper divisors (9909024016).

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

6985894640 is a wasteful number, since it uses less digits than its factorization.

6985894640 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 21678 (or 21672 counting only the distinct ones).

The product of its (nonzero) digits is 14929920, while the sum is 59.

The square root of 6985894640 is about 83581.6644964672. The cubic root of 6985894640 is about 1911.6454338644.

The spelling of 6985894640 in words is "six billion, nine hundred eighty-five million, eight hundred ninety-four thousand, six hundred forty".