6661523880 has 768 divisors, whose sum is σ = 26687232000. Its totient is φ = 1422489600.

The previous prime is 6661523839. The next prime is 6661523893. The reversal of 6661523880 is 883251666.

It is a super-3 number, since 3×6661523880³ (a number of 30 digits) contains 333 as substring.

It is a Harshad number since it is a multiple of its sum of digits (45).

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, 93824245 + ... + 93824315.

It is an arithmetic number, because the mean of its divisors is an integer number (34749000).

Almost surely, 2^6661523880 is an apocalyptic number.

6661523880 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 6661523880, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (13343616000).

6661523880 is an abundant number, since it is smaller than the sum of its proper divisors (20025708120).

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

6661523880 is a wasteful number, since it uses less digits than its factorization.

6661523880 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 190 (or 183 counting only the distinct ones).

The product of its (nonzero) digits is 414720, while the sum is 45.

The square root of 6661523880 is about 81618.1590088872. The cubic root of 6661523880 is about 1881.5879785107.

The spelling of 6661523880 in words is "six billion, six hundred sixty-one million, five hundred twenty-three thousand, eight hundred eighty".