6661409040000 has 3840 divisors, whose sum is σ = 30690390931200. Its totient is φ = 1362493440000.

The previous prime is 6661409039947. The next prime is 6661409040017. The reversal of 6661409040000 is 409041666.

It is a Harshad number since it is a multiple of its sum of digits (36).

It is an unprimeable number.

It is a polite number, since it can be written in 479 ways as a sum of consecutive naturals, for example, 68674319952 + ... + 68674320048.

It is an arithmetic number, because the mean of its divisors is an integer number (7992289305).

Almost surely, 2^{6661409040000} is an apocalyptic number.

6661409040000 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 6661409040000, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (15345195465600).

6661409040000 is an abundant number, since it is smaller than the sum of its proper divisors (24028981891200).

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

6661409040000 is a wasteful number, since it uses less digits than its factorization.

6661409040000 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 213 (or 183 counting only the distinct ones).

The product of its (nonzero) digits is 31104, while the sum is 36.

The spelling of 6661409040000 in words is "six trillion, six hundred sixty-one billion, four hundred nine million, forty thousand".