6781985981540 has 384 divisors, whose sum is σ = 18844479553536. Its totient is φ = 1988292096000.

The previous prime is 6781985981527. The next prime is 6781985981587. The reversal of 6781985981540 is 451895891876.

It is an unprimeable number.

It is a polite number, since it can be written in 127 ways as a sum of consecutive naturals, for example, 2690195480 + ... + 2690198000.

It is an arithmetic number, because the mean of its divisors is an integer number (49074165504).

Almost surely, 2^{6781985981540} 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 6781985981540, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (9422239776768).

6781985981540 is an abundant number, since it is smaller than the sum of its proper divisors (12062493571996).

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

6781985981540 is a wasteful number, since it uses less digits than its factorization.

6781985981540 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 4139 (or 4137 counting only the distinct ones).

The product of its (nonzero) digits is 174182400, while the sum is 71.

The spelling of 6781985981540 in words is "six trillion, seven hundred eighty-one billion, nine hundred eighty-five million, nine hundred eighty-one thousand, five hundred forty".