3947891935680 has 1344 divisors, whose sum is σ = 17551505664000. Its totient is φ = 817715036160.

The previous prime is 3947891935661. The next prime is 3947891935693. The reversal of 3947891935680 is 865391987493.

3947891935680 is a `hidden beast` number, since 3 + 9 + 47 + 8 + 9 + 19 + 3 + 568 + 0 = 666.

It is a tau number, because it is divible by the number of its divisors (1344).

It is a Harshad number since it is a multiple of its sum of digits (72).

It is a junction number, because it is equal to n+sod(n) for n = 3947891935599 and 3947891935608.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 191 ways as a sum of consecutive naturals, for example, 2993094061 + ... + 2993095379.

It is an arithmetic number, because the mean of its divisors is an integer number (13059156000).

Almost surely, 2^{3947891935680} is an apocalyptic number.

3947891935680 is a gapful number since it is divisible by the number (30) 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 3947891935680, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (8775752832000).

3947891935680 is an abundant number, since it is smaller than the sum of its proper divisors (13603613728320).

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

3947891935680 is a wasteful number, since it uses less digits than its factorization.

3947891935680 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1783 (or 1756 counting only the distinct ones).

The product of its (nonzero) digits is 352719360, while the sum is 72.

The spelling of 3947891935680 in words is "three trillion, nine hundred forty-seven billion, eight hundred ninety-one million, nine hundred thirty-five thousand, six hundred eighty".