6981872640 has 176 divisors, whose sum is σ = 23303179008. Its totient is φ = 1780793344.

The previous prime is 6981872603. The next prime is 6981872659. The reversal of 6981872640 is 462781896.

It is a super-2 number, since 2×6981872640² = 97493091122361139200, which contains 22 as substring.

It is an unprimeable number.

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, 343399 + ... + 363161.

Almost surely, 2^6981872640 is an apocalyptic number.

6981872640 is a gapful number since it is divisible by the number (60) 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 6981872640, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (11651589504).

6981872640 is an abundant number, since it is smaller than the sum of its proper divisors (16321306368).

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

6981872640 is a wasteful number, since it uses less digits than its factorization.

6981872640 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 19814 (or 19796 counting only the distinct ones).

The product of its (nonzero) digits is 1161216, while the sum is 51.

The square root of 6981872640 is about 83557.6007314715. The cubic root of 6981872640 is about 1911.2784985691.

The spelling of 6981872640 in words is "six billion, nine hundred eighty-one million, eight hundred seventy-two thousand, six hundred forty".