661441042080 has 864 divisors, whose sum is σ = 2841092392320. Its totient is φ = 137170575360.

The previous prime is 661441042057. The next prime is 661441042103. The reversal of 661441042080 is 80240144166.

It is a happy number.

661441042080 is a `hidden beast` number, since 6 + 6 + 1 + 441 + 0 + 4 + 208 + 0 = 666.

It is an interprime number because it is at equal distance from previous prime (661441042057) and next prime (661441042103).

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 143 ways as a sum of consecutive naturals, for example, 100504390 + ... + 100510970.

It is an arithmetic number, because the mean of its divisors is an integer number (3288301380).

Almost surely, 2^661441042080 is an apocalyptic number.

661441042080 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 661441042080, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (1420546196160).

661441042080 is an abundant number, since it is smaller than the sum of its proper divisors (2179651350240).

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

661441042080 is a wasteful number, since it uses less digits than its factorization.

661441042080 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 6694 (or 6670 counting only the distinct ones).

The product of its (nonzero) digits is 36864, while the sum is 36.

The spelling of 661441042080 in words is "six hundred sixty-one billion, four hundred forty-one million, forty-two thousand, eighty".